I agree, ppl act as though Minato has control over wtf he says, go figure, but I agree with you, tobi's is more superior in that he can choose where he wants to go instantly, you'll have a hard time predicting where he's coming from, but Minato's is faster, and if I'm not mistaken his seals can creep around on their own, and can be set up in advance.
If minato knew more on the workings of kamui then tobi definitely would have died. Tobi's is a better s/t overall, but in battle between ninja's of similar caliber, I think the one with ftg would win more often than not if it came down to purely s/t jutsu. Minato may even be able to warp out of tobi's dimension.