I was about to change the name of the Amiga category into "Amiga 500" because as far as I know different Amiga models have different performance characteristics and the in-game times are not comparable, and the frame rates are also different I think. However I then noticed that some of the current runs were made using Amiga 1200 or Amiga 500+.
Right now the situation is slightly suboptimal. Someone should probably do some rigorous testing first to verify that there are actual differences between different Amiga models, but I'd be kind of tempted to just pick one Amiga model so that all runs are directly comparable with each other. Also see the rules: the last point says "All runs are platform dependent because of different timings and game mechanics" (I fixed a typo there btw, it used to say "platform independent" before).
I would pick Amiga 500 because that was by far the most popular model. And possibly add other Amiga models as separate categories if they are too sorely missed.
Opinions?
I did a little research on this a couple of years ago and the tech geek Amiga gurus are stating that SCR isn't rendered faster on faster Amigas because of the timings of how the polygons are rendered. Both game speed and frame rate are therefor the same.
I myself have played SCR on different Amigas (I had a 1200 with Blizzard 1230 for years) and the game both looked and played the same as on a vanilla A500.
So I haven't found any reason for any Amiga model exclusion since it's basically the same as playing a 60 fps locked PC game on a faster PC.
There are cracked turbo versions out there that have higher framerate and are able taking advantage of faster clock speeds, so that's why the speedrun rules state that the version of the game is important so noone plays a high framerate version. That of course also goes for the recent C64 SuperCPU version (which btw is absolutely glorious).
OK maybe I accidentally tested on a cracked version or something, because there was definitely a noticeable difference in speed and frame rate between Amiga 500 and Amiga 2000.