Note that the old ACA1221 design does have some improvements over the ACA1220, but the latest ACA1221lc has significant advantages over previous 68020 designs due to memory speed.
Note that most of these slowdown issues are solved in WHDload if you enable cache, which is available on any 68020 or higher CPU. It won't solve it for all games, but you'll have the advantage of the faster CPU, combined with fewer bus accesses required, which does the trick for the "big titles" such as Turrican. So yes, the plain 68000 has the advantage of compatibility, but faster CPUs can work around the non-compatibility with their speed. Especially the ACA1221lc has been a surprise to a number of customers, because it's so close to a 68030 in terms of performance, but for a significantly lower price.
I have been debating going for the ACA1221lc. It looks very impressive for a 020 accelerator. Which leads me to another point and benefit of running the ACA 500 + with no accelerator plugged in. The ability to configure the Amiga as a stock A500 with slow RAM for running old floppy games/demos. I heard you guys were working on a feature that would let us 'switch off' the accelerator that was plugged into the ACA 500 +, from the ACA 500 + menu. Any news on this?
Yes, as you say, 'cache' tool tip works for some of the games, but not all. And of course, using any of your 020/030 accelerators will be faster than using the barebones ACA 500 + but I think the ACA 500 + by itself, especially when overclocked is very capable running most whdload games with no issues and 3D games I've tried runs quite smooth.
