The ST-1200 series and of course the GS-1200 get lots of press, but relatively little is heard about the ST-800. (Little is heard about the GS-800, ST-600 and ST-180 as well, but let's stick to the ST-800.)
OK, so the ST-800 only plays and records on the main track, but as owner of a 2-track machine for almost 30 years, I've never made use of track 2 -- but that's just me.
It only plays sound in mono -- but only a handful of machines can play stereo. I don't have a single stereo film in my collection.
It can only handle up to 800 foot reels. Many of my features are mounted on 2 or more 800 foot reels.
It uses the common EFP 12 volt, 100 Watt lamp, but not many Super 8 projectors use a 15 volt, 150 Watt EFR lamp, except higher end ones like the Sankyo 800 and of course the Elmo 1200s. I find that my 800 produces a nice bright image when fitted with my f1.1 lens.
I got my ST-800 a couple of years ago. I think I paid around $100 for it. It was in rough cosmetic condition, since it was most likely stored in a garage -- there was actually dirt/soil from the ground on it. Other than that, it seemed barely used, judging from no wear on the green parts. It just needed new belts, a replacement motor pulley and a one-way wheel for the take up arm from Van Eck. (What would we do without him?)
After get it up and running, I used it for a few films that day, and then set it aside. I just pulled it out again, and it really is a great projector. It really needs to be mentioned in the same sentence as Eumigs and Sankyos for people not in need of a 1200 foot capacity projector.