I really like Efke 25 for portraits; skin tones look a little different from a panchromatic film, in a way that to my eye works really well. But it's a good general-purpose film and I can't think of anything about which I'd really say "no, wrong film for the job". (Well, it's going to be tough to use any 25-speed film for shooting a basketball game or a dim stage, of course.)

Because the grain is so fine, you can use really high-grain developers without any grain concerns. I've really liked it in Caffenol C, and I've seen some very, very good results from Efke 25 in Rodinal. I imagine it would be a winner with pretty much any acutance developer.

-NT