Personally, I think the Monsoon MM2000's are the best you're going to get south of three hundred bucks, from a "quality" perspective. The passive radiators on the sub (it's not ported) give the bass a very tight, clean sound - and the dipole sats have some of the best mids and highs I've ever heard, although the transition from the sub to the mids is poor. The sub also has a limited range (I think it maxes out down around 35hz?), but no more so than the klipsch or logitec, from a practical standpoint. Even those would be marginal from an audiophile perspective. The Klipsch and Logitec speakers are not geared at all towards musical reproduction (more so for gaming, DVD, and anything aimed at getting the cops called on you) and less towards accurate, precise, clean, and rich reproduction of sound. Do they sound bad? No, hell no...but they're just not really that great when it comes to higher end musical reproduction.
If you want my honest reccomendation (assuming QUALITY is your key focus and three hundred is your limit), you should look into getting some comfortable headphones. For three hundred bucks, you can get a pair of phones that'll probably rival speakers costing THOUSANDS more...and although some people scoff at that reccomendation, try playing CS/UT/whatever with a quality pair of headphones, or listening to a DVD, and you'll see that they can literally blow you away.
I've never heard the swans, but they're supposed to be very nice sounding - although I seriously doubt they're a lot better than more popular brands. For three hundred bucks, it's just hard to make a system that sounds *really* good.