I used a 12"(older, American made) craftsman for a lot of years, really nice saw, a little under powered but did just fine with a sharp blade.
For making selfbows I never cut with less than a 1/2" blade, preferring a 3TPI Skip tooth.
Cool block blade guides are a necessary upgrade with this saw. Roller guides are nice but the cool blocks work about as well.
If your saw won't cut straight you generally are using too small of a blade for the wood you are cutting. An exception to this would be a later craftsman Chinese made saw. I had about the same saw as a later craftsman made by Rigid and it was an untunable piece of junk.