M60, from one who has experience behind that gun (air force)
Unreliable, buy a blast shoot.
Never shot the m240G (what we got to replace the m60). Everyone that I knew that shot it said it was loads better than the m60, but it was heavy as a tank, but felt very well built, solid.
Eithor way, Id love to be able to shoot it in a competition.
I hated MGs when I was in the AF, were heavy and annoying (we never shot them, except to qualify with them, dont really want to get into why). If I was being shot at, I would love to have one around (m240). I would loath a m60. Part of the problem with the m60 was that parts for them were becoming scarse, and the examples that we had were so beat up and antiquated that they were just worn out. I bet they replaced the whole gun at least once in the entire lifetime of that weapon, piece by piece, but kept the feed cover the whole time (was stamped sheet metal that looked like it got run over by a tank)
"Where the choice is between only violence and cowardice, I would advise violence."
~ Mohatma Gandhi