It's not that slow, on up to date computer.
I've tried gcc 2.95.3 and it's a snail. I've tried it on a 1.4Ghz PC. Compared to SAS/C on the same computer, it's so slow that I couldn't imagine using it for serious development. Of course such a decision very much depends on your programming style. I like to compile often with full optimization.
Source level debugger: gdb
Well, I'm aware that there is a program with that name in the gcc tree but I just can't get it to work :-) I'd very much appreciate some comments on gdb: does it work, is it any good, what do you do if it reports that it can't find symbols ?