I just picked up a ACM-P2 (soon to be delivered)... I had to sell the WMod+ to get it, but one day I hope to get it back so I can run it in front of the ACM.
Its all about options. With those 2 devices, I could run w/o the WMod+, with the WMod+ as a pre (analog out), or with the WMod+ as a full pre>ADC (SPDIF out). With the 3 options, I imagine I'll get slightly different results. Its should be fun to play with!!!
You're right, there's no "real" reason to get a ACM if you plan to use it as a SPDIF bit bucket, but with this hobby, are any of us really living in reality?!? Its all fancy toys!!! The more buttons and mods and tweeks, the better!!!
I gave the 671 vs P2 long thought. I like the Marantz a lot and thought of going that way first. But the display on the P2 won me over. The ACM-P2 is a "Warm" and there is now a "Trans" P2 (cheaper than the ACM), or at least that's how Doug explained it to me last week.
I went with the ACM since I liked the WMod+ with my TLs. But if you like the TMod you should go with the TCM-P2... Or the Busman-P2 in a few months??? I've heard he's working on P2 mods...
Terry