Having taken care of the speaker-portion of my HT (4xCBM-170s & CMT-340c), I started thinking about what I need to upgrade next. Currently I'm running a pretty basic Pioneer DD/DTS 5.1 receiver (VSX-409) which is about 3 yrs old (it cost $240 at the time I bought it), and a Sony SA-WM40 sub. While I'm pretty satisfied with my sub, I bought the receiver in my newbie days of HT & hadn't done a lot of research. Now I'm sort of regretting the decision and wish I had gone with one of the Denons, Onkyos, or H/Ks.

Considering that a decent receiver these days runs about the same as an HSU sub ($300-$400), if I were to upgrade one of these, which one should I choose? Would I see a significant/noticeable difference with a better receiver than what I have now? Or will the differences be minor? I was also fairly impressed with the Dayton sub from Parts Express & thought about getting one of those & then selling whichever sub I didn't want to keep. Something to tide me through until I can afford a better sub. Again, I know that quality receivers & subs are better then I have now, but just how much better?