I bought the 3700 last year as a back-up board and would not reccommend it. I find it very messy to get any decent registrations set up and whilst I agree with others that the organs and piano used on their own are OK, for me, the horrible noisy keybed renders it unusable except for practice. I am not a pounder but the racket from the keybed offends my ears - even more than my playing!!!

It is a lot of board for the money but I would certainly advise one of the lower end
Yamahas (or others) as more usable.
I will qualify that by saying that I have not tried the later 3800 so do not know whether any of my points have been taken up.

Regards
Trevor