what's the difference other than $70. they put out the same rms power (22wx4) i'm a noob w/ all of this, so i don't see the difference other than a few things. what about the x792 makes it better than the x492, and is it worth the extra $70. My budget isn't very limited, as long as my HU is around $200 or less (like both are) I'm fine. I'm going to be getting some comps in the front and these will be powered by an external amp. I plan on getting a pair of coaxials for the back, and these would be used to "fill" the sound and will run off of the head unit. I'm still debating about which coaxials I want though. I'm thinking about some jl vr 6.5's, any other suggestions would be great on these too. (side question: will these sound okay on 22w rms, or should I get another HU w/ a higher rms output or some other coaxials for better efficency?) Anyway, I'm looking at these 2 HU's and have heard great things about each of them on this forum especially. so, what's the diff. between the two HU's and would the x792 be worth the extra $70? thanks in advance