This map is quite massive, I don't understand where the author got "a nice DM map good 3/4 ppl" structurally it would have no problem suiting 12 players or so. It's sort of a bland map, nothing really extraordinary or stylish about it. Though it does have a good design and layout to it, however some of it jumps can be a little bit time consuming with the stacks of crates and all but that's really of no concern to anyone who can rocket jump even half-way decently. With its wide halls, huge rooms, and high ceilings it just cries out for the grappling hook.
If you like the hook this is a map you may love. If you're not so fond of the hook it's still a good map to check out.