I've been considering a purchase of Polk speakers for a couple weeks now, and had the oppurtunity to listen to a pair of RTi8's and RTi12's last night and A/B them.
My initial reaction on hearing them was that the 8's seemed to put out a LOT more bass than the 12's, but the 12's were much clearer in the mid and high ranges, with tighter but less bass.
I suspect there was an issue with placement of both the 12's and the 8's, as the set of 8's was pretty boxed into a corner and could have been amplifying the bass due to its position, but the 12's seemed to be placed right, and to be honest I was a bit disappointed by the bass output on them.
Does anyone have any insight on why the 12's would have so much noticeably less? The store I was at didn't have any LSi15's yet, which could also conceivably fit my budget. I can't wait to hear them!