tl;dr: Five stars for sound quality (especially considering the size of the speakers), but a 3 for the price (you still pay for the Bose® name).
For a very long time, I've used my computer, with a 24"+ display, as my TV, computer, DVD/Blu-Ray player, Xbox 360 setup, etc. Because of this, I had my 5.1 surround sound system, with some very nice speakers and a great sub, plugged into and surrounding my computer. It enveloped me in the most amazing aural arena I've ever experienced.
However, after marriage, I moved the surround sound system into the living room, along with a new TV and the Xbox and and Apple TV. That means I went back to the stone-age days of computing sound, using the tinny built in speakers on my iMac (now MacBook Pro). For a while, I was satisfied with this, as I didn't do a lot of music listening or gaming on my Mac.
However, now that I'm freelancing, that doesn't cut it. I've gone through three sets of speakers before finally settling on the excellent, but pricey, Bose Companion 2 Series II speakers.
Let's cut to the chase:
For my purposes, these speakers hit a sweet spot. Too many 'computer' speaker sets (especially those with subwoofers included) tend to crank up the bass and muddy up the vocal range, likely because they're targeting shoot-em-up gamers who like explosions.
However, I find myself listening to classical, rock, alternative, country, jazz, etc. music, and also watching the occasional film in here (usually while my wife's watching a daytime talk show on the home theater system...).
These speakers seem to be made for jazz, though they are a bit flat on the highest notes (think a double-C from a trumpet). They can be heard from a room or two away if I need to turn up the volume, and they do fill a medium sized room very well. For a small gaming setup, or a small room, I'd even consider them over a stereo system.
Interference / Static
One of the biggest problems with any 'computer' speaker set I've used is that, somewhere in the system, adequate shielding and sound signal isolation is not supplied, and the resulting hums, buzzes, and hisses are like daggers in my ear. Especially considering I'm living within one mile of four radio towers (I could clearly receive one of the FM stations through one set of Altec Lansings I tried, even when it was turned down all the way.
These speakers exhibit absolutely zero interference, though there is a slight hiss that won't go away, no matter where I plug them in (some outlets are better than others). It's enough that I'll turn off the speakers if I won't be using them for a while, but nowhere near as bad as any other speaker set I tried before these.
Setting up the speakers is pretty simple. The right speaker has a power jack for the included AC adapter, as well as two RCA inputs (left/right), which allows you to plug most any home sound source (tape decks, cd, dvd, etc.) or computer into them (an RCA to stereo 1/8" minijack adater cable is included).
Back of the right speaker.
The only downside is that the left speaker's cable is hard-wired into the speaker, making it a tad bit more difficult to extend the distance between the speakers. But it was long enough to run from one side of my desk to the other, behind the desk.
The volume knob is easy enough to use, and gives a good range of volume (from don't disturb the napping baby, to wake up the upstairs neighbors), and the headphone jack offers a convenient way to bypass the speakers without unplugging them from your sound source. They drive my large Audio Technica cans pretty well, but don't do much as a headphone preamp.
The major downside to these speakers is the price. I think, for the quality and sound stage they provide, I would be happy paying $50, maybe $60. But $90? That's pushing the range I'm willing to pay for a secondary set of speakers (my mains being the 120 lbs-worth of speakers in my home theater setup).
Since these speakers are Bose, you're paying about a 20% premium for the name. But I'm okay with that, because the other top-tier speaker manufacturers do the same, at least for their good sets of speakers. (I'm thinking of you, Klipsch and JBL!).
I'm happy with the speakers. I bought mine at Best Buy because I had some Reward Zone gift certificates, but I would otherwise buy them at Amazon. You can buy them for about $90 on Amazon.com: Bose Companion 2 Series II speakers.