RTi15's???? Have you demo'd any Polk speakers. I actually prefered the RTi12's to the 15's myself, but I didn't get to do a side by side, so other factors could have been involved. If it were me, I'd go with the RTi12's...
Man, they are almost as sweet as it gets in that sort of budget. Of course that only gets ya two....
On the Infinity - H/K side, I like Beta 50's better than the much higher priced Prelude MTS.
I like the RTi12's better than the BW's and the Swan 6.2's, to be honest.