i think you want the samyang 14mm. I have one that i use for the sort of silly stuff you can do with 14mm, and astro shots. I've yet to aim it at the stars because i've been so busy, but i'm pretty pleased with it for the more earthly shots i've taken with it.
I took some shots of a wedding couple last night with it. i had to convince them to step closer, closer, closer still. "i swear, i'm not just taking a photo of your belt buckle!"
I think you're right, I just have two questions, does the lens have a hard stop at infinity and is it sharp enough wide open?
Yepp it does and it sure is performs wonderfully wide open.