I'd hold out for the Cobb.. I have a dh.. And it's great but, I'd hold out if you can afford it.. And your testpipe/inlet will make you very happy for sure!! Best mods for the $$ and we get lots of used DH on MOCC you might wanna check..
I'm assuming you're talking about the Cobb AP? I was always under the impression that the AP can do datalogging, but not on the fly like the DH can do. The Cobb is on my list, but I'm going to hold off on it for a while.