@stuntmachine - I was looking at the one on e-bay.
I've been extremely happy with my ACA, though it does work more smoothly with 3.1 ROM's.
I've also been REALLY happy with my ACA (1230/28). Great card. I know some people have had "timing fix" issues with some of their 1200's, but mine didn't need any.
(It's not specific to the ACAs, and related to the inconsistencies of Commodore's quality control, but some 1200's need a "timing fix" (removing a few resistors), and a lot don't. Just something to be aware of...)
As for 3.1, one of the nice features of the ACAs is that it lets you "softkick" a ROM. So you can off of a 3.1 ROM. You do need a copy of the ROM and a line in your startup-sequence. Also, you need to set a jumper on the ACA to tell it you are running 3.0 originally.
Of course, a actual 3.1 rom in your machine is a bit nicer, but the option for the softkick is nice to have...
desiv