According to that graph he's pretty similar to the congressman we just dumped. (Joe Schwarz) However a graph doesn't really tell the whole story because Schwarz was a liberal and I know Thompson is no liberal.
In any case I'll keep an open mind but Hunter is still my first pick.
They are pretty good about properly recording votes. How they use those votes to put people on their grid sometimes amazes me.
Thompson wasn't big on tort reform which the site took as a non-conservative position. He had one or two really strange votes, like one where it seems he was against restricting minor's access to violent movies. That could either be seen as an anti-family-value position (which is how the site seemed to treat it) or it could be a strong libertarian position.
He's not perfect. He's the kind of person where you would have to make some compromise, but it's what they meant when they defined the word compromise, not the "sacrifice all your principles" kind of compromise you'd have to do for Rudy.