100 round belts were the most common for infantry squads to use. It can be easily draped around your neck and then tucked into your y-straps or belt so it doesn't fly around. The standard inf squad would have an AG with the MG, who was the ammo carrier/assistant gunner, and not only would he have 1-2 cans of ammunition, but the rest of the squad usually had belts of ammo draped around their necks as well (Depending on supplies of course). The belt doesn't cause any more issues for feeding than the drums did either! The drums kept the belts from getting dirty but had a whole host of issues themselves, and for a suppressive weapon, the drums were shunned in anything but fixed/aa positions. You almost NEVER see them being used by infantry units (They were much harder to carry around than belts)
That being said. I have only hauled around an MG34 with a belt one time, and the gun kept jamming, but I have done exactly what people are saying caused jamming/increased time to deploy with an MG42 and a 100 round belt, but without all the problems you guys are talking about, and done this around 12 times now. All you do is wrap it around the gun once, and flip it over once you are deployed. The belt also makes for faster reloads than the drum too.