Finally got SFIII up and running on MAME. It is from 1997 and runs on Capcoms CP System III board, a very rare and unsuccesful system that were only used to develop 6 different games, 3 of which were SF games. This game looks absolutely wonderful, with super-smooth animations and very detailed backgrounds.
Completed the game with Ryu on 4/8 difficulty and got the score: 1487010.
Initially, I started playing on difficulty 1/8, but when I reached Gill, the end boss, he seemed to be unfairly difficult, and I suspected a SF4-like situation, where the end boss difficulty doesn't really change with the difficulty of the other characters. So I restarted on 4/8, and sure enough, he wasn't more difficult; however, I was in better training than the first time, so he had to eat it. And eat it he did.