The RF-3's are VERY SET-friendly!
I have used mine with a pair of 300B-SET's for about a month, and i'm very satisfied.
Before the RF-3's, i had a pair of "Magnepan 1.6QRse" and i am very impressed with how the RF-3's handle the music were the Magnepan's excelled.
But the Magnepan's were MUCH to low on efficiency, so my love of Rock'n Roll was suffering too much
The Magnepan's sound very transparent on female vocals, but the Klipsch is not far behind!
Considering the price, the RF-3 is a steal!