Yes, always works fine. No performance issues for Lemmings, at all.
(Unfortunately, I'd have to pick other options for many other games...)
However, I've never gotten ONML to run correctly on it, but it's just a downloaded version... (Error is something about not being able to read a data file from disk, though ONML runs basically fine in XP, though without sound.) But I suspect this is completely irrelevant to you