Super solid, simple installation if you know what you're doing - Midwest Industries Gen2 Two-Piece Free Float Handguard

This thing is a beast. It's light but extremely solid, and I wouldn't have guessed that it would be so solid being that it uses the standard M16 barrel nut as its mounting platform.

What that means is that you need to have a delta ring installed on your rig, and then disassemble it (remove the circlip and spring) in order to use this hand guard.... or get a M16 style barrel nut (just the nut) and remove whatever is currently holding your barrel on. This of course means you will need to re-time your gas tube or if you were using a different free-float system, time your tube for the first time. It's not AS hard since you don't have to deal with the spring, clip, or D-ring. Just have to time the barrel nut teeth.