I own the Legend LX supreme yolk version ACD and decided to change out to the DIN... After talking to the tech at my LDS he pulled out the schematics on both versions of the DIN one with the ACD and one without.
The price is about $60 bucks more for the ACD... He pointed out that within the DIN version of ACD there are two additional O-rings, that places you with a total of 3 O-rings, there could be a failure waiting to happen.
With the regular DIN without ACD it's one simple O-ring that get driven all the way back to your HP tank, one failure point.
I was sold on that since I want to get the XTX 200 Apeks as my primary reg when I go doubles. If the Brits rely on Apeks without the ACD, then you have my vote.
I take home my reg dry even when it was ACD yolk and then I clean it while attached to my HP tank, I hose it down with pressure from my garden hose to remove all containminants.
If it works why fix it? Dozens of divers dive Tech without ACD and there is no complaints of them wanting to have ACD.
If you like ACD just go with it, if you think tech, you might think again...
MG