There's some brilliant and careful engineering going on here. But it's not perfect, and not for everyone seeking a Bluetooth speaker. Certainly, at its original list price of $250 US and for the sound QUALITY, this was designed as premium product oriented toward the high fidelity enthusiast. It sure has a lot of functionality, as well.Let's start with the good stuff:It has a really balanced, rich expansive sound. Even if you're a distance away, say, in the next room, you will be thinking that you're listening to real music. You can hear the micro-dynamics and detailed midrange that are ingredients in a higher end speaker. This is not a speaker that you have to be right in front of to hear the balanced sound.Functionally, this unit will allow you to not only play music via Bluetooth from your phone or tablet, but it has a 3.5mm input for which you can directly input a sound source (CD player, phone, etc.). This will get you BETTER sound quality, as direct sound offers a better quality signal than Bluetooth.This unit will also charge your phone or tablet's internal battery. What's the big deal about that??Well, while some have complained about this having a proprietary charger. But that's actually an advantage here. It charges direct current (DC,rather than alternating current, AC). This means that it can charge ANYWHERE in the world and can adapt internally from 110volt to 250volt. The unit comes with outlet adapters for use all over the world. Wherever you're going, you're all set for charging the unit. Do you have the proper wall converter for charging your phone while in Paris? You may not. But plug the Riva into the wall, and you can plug your phone into the Riva for charging. Clever design.There is a lot of technology and design in this unit. There are 7 different drivers (speakers), 3 active and 4 passive. And this was definitely designed for great/accurate music reproduction. There are no exaggerated bright highs, nor big tubby lows. That means that this is not for head banging music. This unit is going to be heard with jazz, classical, folk, vocal, musical theater -- the more nuanced the better. I mean, this speaker conveys acoustic instrument textures beautifully. And again, you hear the gentle pushing and pulling of instrumentalists and vocalists that give the music life, even from the next room. Part of this has to do with drivers on all 4 sides of the unit rather than just in front.Riva also has designed remote apps for use on Apple and Android devices. It certainly worked in the next room about 30 feet away.The Riva S comes with a padded nylon carrying case (and it has a carabeener type plastic loop which you could use to carry around portably on a belt). The case doesn't have space for the accessories like the cables and whatnot (The Riva S is supplied with RCA-to-3.5mm and 3.5mm-to-3.5mm cables, as well as the walwart and adapter faces for the wall outlet. The Turbo X bag, which is a separate purchase for those that purchase that unit, DOES have an extra pocket for accessories.).The downsides for some are twofold, one major --This just doesn't sound very loud. At its top volume, it's adequate. It's probably enough for my purposes, but if you really want room filling sound, you'd probably want to look at the Turbo X, though that unit is over twice as large. The Riva S is really designed to be a compact package which won't take up much room in a suitcase. If you're willing to deal with only moderate volumes and really want natural, realistic sound, this is a great unit. If you want head-banging power, or sound that really saturates the room, this isn't the unit for you. Interestingly, as I mentioned before, the multi-directional speaker design makes it sound good pretty much wherever you are in the room or the next room.Furthermore regarding the sound, due to its small size and natural-oriented sound design, there isn't a whole lot of bass impact in this unit. The bass is there to a modest degree, and reinforcing the bass by putting the unit near a wall or a corner will significantly help, but there's nothing remotely approaching gut-feeling bass response here. However, listen long enough and you'll likely appreciate the nuanced balanced sound. Knowing that this is not going to be your main speaker system, and you'll get used to what things it does so well.Part of the unit's musical capabilities is that the designers know that there has to be capability for peak dynamics. When the music needs a dramatic push of power, the unit has the power to deliver on that briefly. The difference isn't going to be huge, but it's the ability to convey the musicians' intentions is what makes listening to this rather compelling in the long run.The Riva S has a power mode, which boosts the power to make everything louder. But doing that squashes the dynamics. Instead of having that living, breathing feel to the music, everything seems pushed to the wall. It's the equivalent of digital music being mastered LOUD, so that everything sounds equally loud. At first it's impressive, but the music loses some of its life. So if you merely need some extra added volume, it can deliver somewhat (within reason), but you will also lose some of the musical qualities of the Riva S. Also know that it has a turntable mode in which you can plug in a turntable and it will boost the volume to accommodate the low built-in output of a turntable (a turntable cartridge puts out a tiny level signal, which ordinarily needs a separate preamplifier called a phono stage.).The other thing that you may want to consider is its battery life. A smaller unit requires a smaller battery and that means less power and less battery life. The company touts 13 hours, but that's when played at 70% volume. At 70% volume, it's really anemic sound unless you're literally feet away. At 100% volume (and I don't mean the Power Boost function engaged), you still maintain ALL of the great musical qualities, but you're probably talking about 5 hours before needing a recharge.So if you're willing to live with its limitations, mostly the lack of ability to play loud, this is a sweet unit. At the current price (as of 12/24/16) of $99, it's a bargain considering that it was originally selling for $250. The Riva Turbo X, considerably larger, will cost you about double if you add the carrying case, a separate charge. Some say that, at equal volume levels, that the Riva S actually sounds better (particularly in the midrange) than the Turbo X. But you'll get a lot more volume out of the Turbo X. Either way, these are speakers aimed to the high fidelity enthusiasts. Don't be fooled by bright highs or big bass. Listen for the pitch, the precise notes of the bass lines. Listen for how natural voices and cymbals sound. Does the high end sound tinny. Does the bass sound tubby and flubby? You won't get that with Riva sound.So for the money, I give the Riva S a good thumbs up. It does pretty much everything I would want from a Bluetooth speaker this size.A small niggle -- I discovered that the first unit's top was not precisely straight. When lifting it up from the the back and front near the top, I felt a sharp edge where the top of the unit was slightly overhanging. I wrote Riva. They asked for photos. I took photos that showed the top being slightly askew. They told me that this was not how they should be and suggested I return the unit for another one. I did that.The 2nd sample had the same issue, and it also had a number of light scratches on top of the unit (as though it had been a returned unit). I sent it back as well.I decided to order one directly from Riva. They checked a few units and they all had that slightly askew cover, according to them. But Design determined that it was within acceptability and not a defect after all. It IS small, but feelable. I still ordered another unit directly from Riva. This slight lack of precision fit is not a deal breaker. Not for $99 including shipping. But given how slick this unit is otherwise, it's a hair disappointing.