Right! So. I'm in.
Firefight in ODST was my all-time favorite aspect of Halo. Ever. I was
totally into it, spending hours a day practicing solo, learning everything down to the patterns of the waves, exact strategies for each enemies, and corresponding strategies for each enemy in each map. After getting Endure with a group of 3 friends (who were all very bad at it...) we must have tried at least 15 times. In the end, when we got better, we would be losing
so close to the end - about halfway through Set 4
Don't worry though, I've personally gotten really good at it. From all the practice trying to get endure, I was able to solo the rest of the maps and get each and every 200k points achievement. So I should be good enough to try this again
Anyway, I already have the Endure achievement, but I'd love to help you out with my experience and advice to help you get yours. Count me in!
P.S. Alpha Site. Its X-shape allows two teams of two to aims down two natural choke points. By the time enemies get into the center, they'll be blasted by the full force of a 4-man crossfire. Alpha Site's shape is the most defensible by far, and makes it impossible for enemies to sneak up on you, or surround you.