As not all ar10 stuff is as interchangeable as ar15 stuff it's probably worth thinking about what is going to be posable to get parts for down the track.
They also don't all take the same mags,not a big deal if your importing yourself and bringing a large pile of mags on at the same time, but a big issue for some as mags get lost and damaged-I sold my first ar10 years ago as mags were like rocking house shit.
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