I'm not exactly sure what you mean but if you mean that the VXL-030 fits in an A500 you are correct. I had (or still have rather in a box) an A500 with a VXL-030 and it worked well. The downsides was that I had to clock the 50 Mhz 030 down to 43 Mhz for it to work, if I had it at 50 the computer wouldn't boot at all. And the serial-port had some serious problems too, it couldn't cope at all with the speed.
Put the card in an A2000 and it's a different matter so I suppose the motherboards in these 2 are somewhat different.
Another thing is that without the RAM-32 it is absolutely useless. It has no gain whatsoever so getting a VXL-030 without that is a real waste of money.
I tried for quite some time to find the modules to upgrade my RAM-32 from 2 Mb to 8 Mb but had no luck at all, except for one place but there they would have cost me about $30 a piece, and you need 16 of them.. so you can easily understand why I didn't buy them.