If they don't say 'Best' on them, then they're not. I bought a full-gasket set from Speedway about 2 years ago - and they were a bit tricky on their website, the wording made it seem like I was buying Best gaskets. They used a lot of the same lingo that Best uses - typical 'Speedway' when they're cloning something - not quite the same as the originals.
The 'clones' by Speedway were nowhere near the same quality as Best - the fire-rings were all goofy, the material was too thick, etc.. The timing cover gasket was .025 - .010 thicker than it should have been (screws up cam thrust). I sent the whole set back to Speedway and bought 'Best' gaskets -- they're named that for a reason! LOL
Here is what I sent them -- they were very nice, refunded my money, etc.. The lady said "nobody ever complained before" . . . maybe not, so I didn't mind being the first:
Here is the document I sent them:
Speedway Gasket Set Issues.pdf