I have some experience with the Tsi series and they are alright. At high volumes, I have heard tweeter breakup. The Tsi200 bookshelf speakers are similar to to 300 towers and would save you some money to put into a better sub.
IMHO, the TSi series is really made to be put on a Best Buy sales floor and sold to the masses. Polk Audio (and a lot of other brands for that matter), make more refined speakers that are sold at boutique shops. The speakers aren't necessarily more expensive, just with a different target audience. For example, Klipsch has a synergy line of speakers that overlaps in price with their reference line. The synergy speakers were/are sold to big box stores and online retailers but were regarded as pretty poor speakers. Their similarly priced speakers in the reference line, however, were much more highly regarded. Same price, two different design goals.
I would get some music you are familiar with, or look for suggestions online, and just listen to as many similarly priced systems as possible and see what you like.
