I don't know much about dancewear yet, so I did some digging. The MT10 seems to have been around forever; as best I can tell from the rather dilapidated tag, the tights I wore waybackwhen were MT10s. What's the difference? The MT10 is 100% nylon, while the MT11 is 92% nylon and 8% spandex.
Oh... and Capezio stopped making the MT10 style in favor of the MT11 about two years ago.
I really can't bitch too much about a brick-and-mortar store stocking out-of-date styles. Between the comparative rarity of male dancers and the ease of ordering off the 'net, I'm sure they don't sell that many men's tights. Still, it's points in favor of Artistic Dance Fashions that the guy helping me commented that I'd like these (the
Speaking about styles being around forever... Capezio advertises three styles of male dance belts on their website: the N5930, N5933, and the N26. My current one is (I know you're just itching to know!) a N5930. One of the two I wore waybackwhen was a style 26. It seems things change slowly in the dance world. Given that the half-life of knowledge in my career field is about 5 years, having something in my life that changes slowly is a comfort.
I should note that I'm not particularly attached to the Capezio brand. They just seem to be the brand the stores I've shopped in carry. And unlike a pro dancer I don't live in these things so they tend to last, which doesn't give much cause for experimentation.
Edit: Seems like lots of people are interested in men's dance tights, as I'm getting a lot of search hits on this posting. If you continue to read this blog you'll find that when I bought some MT11 tights I realized the style I had been wearing were Capezio style 5945, not MT11. Thus I've edited where necessary. Sorry if the edit makes it harder to read.