Polk... TSi or RTi A's?

[Jmobie]

I am currently living with my parents and attending grad classes, and helping them rebuild their HT setup with Infinity speakers, since most of them were already Infinity. My dad has had these two Yamaha NS-A1638 towers for the last decade, and so I've always thought the fronts of any system should be towers. Anyway, back on topic. I have listened to Polk speakers before and really like them. Whenever I find my actuary job and get my own place, one of the first things I plan to do is get a nice 5.1 setup. I believe that a 5.1 setup for the price of a new fast computer is reasonable, so about $1000, give or take.

How much better are the RTi A's than the TSi series? Since I'm not into buying separate amplifiers, is it better to just get the series with even more clarity? I was considering the CS10, with two TSi 500's as the fronts, and two TSi 100's as the rears. But then, I was thinking about the CSI A4, with two RTI A3's as the fronts, and two RTI A1's as the rears. Then later down the road, get a pair of A5's or something comparable. It seems a lot of people love the A3's as their fronts. I would definitely purchase a subwoofer either way. I just wanted to know your thoughts. Thanks.