I give it a 9 :-P
PS ... Love that Secret room. Halarious
8.5 for me.
The main scene that shows up on this screenshot it's the more good looking place of the map.
On the inside, some places look very similar.
8 from me too.
The outer area in particular is nicely constructed, but the walkway is a bit small to be useful (and I hate the fact that there's no way back up besides rocket jumping). Health is also a bit sporadic. My other issue would be the presence of two RG clips; that's tons of firing time compared to two clips of other weaponry, and they're right next to eachother no less.
Some common first map/learning issues, but don't let that scare you; it's worth the time to check out.
P.S. 8 from me. I know I give everyone an 8, so sue me :-p