I have that board and it is a fast, stable and nice board. The 33MHz 68020 gives about 5500 dhrystones which is more than some 68030 A500 accelerators. The on-board 32 bits ROM is a nice feature compared to the 16 bits original ROM. There is room to fit your hard-drive on the board. I regret that it won't work with any DMA device one the side port such as the A570 or A590.
However, it will not fit with an Indivision ECS because the Viper520 covers the Denise. It might fit underneath with one or more CPU risers, but then you will loose the upper shield and may be unable to close the A500 case. It would require serious modding to take the Denise socket elsewhere with a ribbon and put the Indivision elsewhere. You could also sacrifice the Denise itself (not putting it back on top of the Indivision) but then no more output from the DB23 port or component RCA.
