I owned an ACA1230/42 and I can say it's a piece of crap! Very unstable design, especially with motherboard rev 1b & 2b. Also, the ACA630 is not compatible with a lot of games due to the SDRAM memory. Also, you can't change them if the SDRAMS are getting fried or something, because there soldered to the board. Why didn't Jens use a plain oll' 72pins EDO socket!?
Another downside is te lack of an (optional) FPU. I know most of the people don't use the FPU anyway, but a certain percentage of us does. Think of JPEG loading in AdPro or faster 3D rendering. OK, you can say "wy not do that kind of stuff with your PC (WinUAE), because it's faster." But I (and others aswell) like it when I see my beloved Amiga work hard to do the job!
Google "aca1230/42 problems" to see how many complains there are about the ACA's from Jens...