I disagree actually, because I think Airfield by a mile is the best map I have played and maybe one of the most impressive maps I've ever played in any game ever.
Don't even bother with it unless you can run in x64 DX 10 mode, because the map will crash constantly otherwise. It uses more than 2 gigs of ram and has an actual playtime of over 2 hours. Not only is it big, but it also manages to keep the experience fresh both visually and gameplay wise throughout the entire map. It also has some really huge views and interesting physics use with telephone pole cables actually being dragged down with the poles if you run them down with a jeep.
It doesn't wow you with the most impressive stuff right away but if you stick with it for more than 10-15 minutes you will probably get hooked and in the end be very impressed by the scale of what's possible do in Cryengine 2.
Personally I have played through the entire map 3 times which means that I have spent more time (and had more fun) with this one map than I did with most FPS games released in the past year.
But don't get me wrong, Vulcano is also a fantastic map, it's just not the same sort of "showcase of what's possible on a modern pc" that I think this map is.