Etude of a Street Corner might not be the best looking fan mission you can play today (wouldn't really call it ugly either, the brush work and texturing are actally very competent!), but trust me, the layout is a lot of fun. By the way, it's a relatively small and short mission, and enemies won't cause too much trouble for you - but I'd say the main attraction here is exploring the map for loot (and well hidden secrets) anyway. Atmosphere wise there may be much better fan missions out there, but a lot of decent stuff is going on here as well - not to mention that it always makes me happy whenever a decently crafted small mission gets released, so...

Highly recommended!