Polk has a very nice, smooth and detailed sound... Boston does tend to lack some warmth in the midrange... Infinity is very bright, as in a lot of highs... which tends to be too much for some people, almost harsh.

Anything can be compensated for with some good equalization and proper tuning.

A good subwoofer to look at (if you end up wanting or getting one) is the Infinity Basslink... its small in size and puts out a good amount of sound. Its a great addition if you just want a little extra low end to round out great sounding speakers.