The original M60 was definitely a flawed design, but the latest E6 model appears to fix most of the problems.
Don't buy it: the M-60E6 is nowhere near the machine gun that the M240G/E or even the PKM are.
Some background:
In 1995, I took over the Infantry Weapons program for the Marine Corps and found out that my predecessor, Major Jim Nelson, had originally been tasked with repairing the flaws in the M60E3 - it was the latest iteration and it was melting barrels. The army had specified that the latest version of the M60 had to have a thin, wispy barrel so that they could have a "walking fire" capability for their medium machine gun and the Marine Corps was stuck with an MG that shot through sides of its barrels after only 400 rounds of sustained fire.
Major Nelson found out that the army had 5,000 FN-MAG machine guns in storage at Anniston Alabama that they were not using (they were originally bought for the new version of the Abrams) and had them transferred to the Marine Corps facilities at Albany GA. He used half the money budgeted to fix the M60 to alter the M240s from the armored vehicle configuration to the ground configuration (hence the "G" in M240) and suddenly the Marine Corps had the world's finest machine gun for its infantry.
Not so fast. Sen. Cohen of Maine blocked everything in favor of SACO Defense (of Maine). Jim Nelson actually carried one of the M240s to Congress with the Commandant to show Sen. Cohen and explain. They had a shootoff between ten of each type of machine gun and the M240 wiped the ground with the carefully factory-prepared M60s in all categories - so we got the M240G.
The Marine Corps carefully rewarded Major Jim Nelson in its usual way: his superior gave him a lousy fitness report because he really pushed the envelope in contracting and because of all the hate and discontent his move caused and he was passed over for Lieutenant Colonel. Let no good deed go unpunished!
My only role was to read all of this correspondence in my newly acquired desk and then I wrote Jim up for a Meritorious Service Medal, since he had single-handedly ungraded our combat capabilities with that excellent gun. I also got a copy of the citation to the promotion board and he was finally selected for promotion.
Unfortunately, he never got that medal - the Marine Corps gave us a commanding general that wouldn't approve a medal for an action over three years before - but at least Jim got promoted.
The M240G has more than proven itself in combat in Iraq and Afghanistan over and over.
Wish we'd had them in Vietnam. Little B*stards would be voting Republican today.