Sweet! (I would say that's an awesome deal. I paid a lot more than that for mine, lol.) I used to have a 10S. Good camera. I gave it to my sister-in-law, and she has never used it once. :er: I wish she would give it back...
The 10S can shoot film with no sprocket holes, which can be handy (you can find non-perf bulk film cheap)... Also draws no battery power while the shutter is open, so all night exposures are no problem.
The only thing I didn't like about it is that all of the settings go back to the defaults when you turn it off. It's always set to f/5.6, 1/125 (I think) when you turn it on. I always half liked that and half hated it. lol.
There is a lot of information on it here:
Canon EOS 10s (EOS 10)
Some people might find only having 3 AF points limiting, but I pretty much always found that one of them was right where I wanted it. The viewfinder was pretty good, from what I can remember. Funky meter though. It shows " - " when you're under exposed, " + " when you're over exposed, and " +/- " when you're zeroed out.
If you want to meter something white and set it for two stops over exposure, you have to zero it out, then count the clicks of the wheel till you go two stops. It can only adjust in 1/2 stop increments too - which isn't really that big of a deal...