I purchased this for my A500 Rev. 6A. I have 3 ROMs: 3.1, 1.3 and also a DiagROM chip. The first problem I encountered is the position of the 5 pin connector from which you connect the wires that leads to the dial knob (to select the ROM). This is an angled connecter with pins soldered underneath the board. There isn't much room left to connect the wires in this case and the RAM chips are in the way. I had to desolder the pins and put them on the top instead. When the board is fitted, I noticed that it would need some support underneath. It floats above the A500 motherboard and the A500 ROM socket is the only thing supporting the board. Considering that the board might hold up to 4 ROM chips, I used some small rubber feet (pads) so that it can sit on the Fat Agnus chip PLCC socket giving it better support.
I like the board in terms of functionality. However, for an Amiga 500 installation, I think that the points mentioned above should be considered.
To be fair it does specifically state on more than one occasion in the description that this was not specifically designed for an A500 and we have no idea if it would fit in an A500. Thats why the full measurements are given with the caveat "whether it would physically fit into the casing you would have to investigate yourself". All that is stated for certain is that it physically fits in an A2000. We have sold dozens of these kits to AMIGA owners, presumably for various models, and we have never had anyone get back to us complaining of any issues.
The board doesn't really need support underneath, unless you happen to throw your Amiga down a flight of stairs on a regular basis! As it says in the listing, this was originally designed for a Kawai R100 drum machine which always have at least 3 or 4 ROM's installed. Having sold over 100 of these kits to R100 owners, and done some fairly robust testing on them, the only way its going to come loose from the socket is if the unit was dropped from the kind of height that a loose ROM switcher would be the least of your problems! The only real issue might be if anything has ever been plugged into the socket that uses square pins instead of the machined round pins used on this board, as square pins tends to bend the socket contacts making their grip unreliable.