I've had both. I've tested both. I'd rather have the AQ.
Someone said its the old style M4 and a Zenon board. Ok. Is that bad thing? No. It's a good thing.
I'm not going to go into a pissing match about DD amps vs. DC because I really like DC. But I don't run their amps for a reason. The price to performance isn't there (for me). And I'm not doubting mylows' clamp, but I couldn't get that out of mine.
I've never claimed to be an amp engineer or repairman. But I've owned and tested a lot of f'n amps. Anyone who questions AQ's reliability is a retard. The AQ2200 remains as one of my favorite amps. It's a straight up warrior. And even if the DC2.0 and the AQ2200 were the same price, I'd still get the AQ.
M4 vs. a DC3.5? I'll take the M4, please.
And I'm not biased. I use what works. I think it's awesome that mylows is cutting you a deal. Kudos to him, but before you pull the trigger on that kind of money, give Jack Sisco a call about the B2 Audio Zero.1.
At the end of the day, they're all good amps. If one fits your eye better or your budget better or you want matching gear, roll with it. You can't really go wrong. Mylows is a stand up dude but B2's customer service is 2nd to none and that's a fact. DD's? Well... Not so much. AQ was cool the couple times I've dealt with them.
Let me just say that I'm not bashing DC at all. I love DC. And their amps are top notch. I think they undershot with the 2.0 and 3.5 though.