There are some manuals on line, but bewarned...they are biiiig.
I've been using the reveb measurement graph in my Pioneer amp and it's quite interesting to read. There is a spike in my room at 250hz on all channels (standing wave?!?), but it is several times higher coming from the centre speaker.
Pioneers graph only covers 9 frequencies, so it would be good to see more detail via REW.
My plan is to use REW to make some changes to the room, then finish off with some EQ to touch things up.