I bought one of the 24mm's in 2014, but only used it briefly before putting it on the shelf. The rendering never really pleased me. Dave described it really well. It's technically just fine, but it's too clinical for my taste. Of course it can take great pictures, but it just shoots what you point it at without adding any special character. I know many people prefer lenses that way (one person's "character" is another person's "flaw"), but not me. It's the reason why I don't use modern lenses, which tend to be technically excellent, but artistically dull.
This was my favorite picture I took in the brief time I used the lens, of my cool uncle driving us through the desert in his jeep.
My copy also has a loose front element. It doesn't seem to affect the pictures, but the glass front element wobbles if you hit it with a blower. I can't figure out why. Everything is tight, as far as I can tell, and the lens shows no sign of ever being disassembled, but it's like there's a shim missing somewhere. Anyone else have that issue?