I have the RF-83 system, minus the sub which I already had from another manufacturer. I came from Polk speakers, and really like the Klipsch sound in a sound treated basement. If you listened to them and liked them, then I say go for it. I'm running mine with an Pioneer Elite 74txvi, and it seems to be plenty of power.
As for price compared to the RF-82's, is it worth the extra money? Nope. However, here in Indianapolis I went to Ovation and they had a buy one, get one free sale on the RF-83's, so I got the pair for $1,250, and get an incredible deal on the rest of the package as well. Is it worth the price retail for the set? To be honest I wouldn't have considered it. I didn't want to spend over $2,500 for the 7 speakers, not including the subwoofer, and for that price, I couldn't find a speaker that I liked more.