Helldivers 2

Haven't tried the HMG yet personally, but all of my group that gave it a spin tonight said it's junk. Recoil is wild, mag is small for a high-RoF weapon, and it doesn't one-shot chafe. We don't see description tags for support weapons, but if we did I bet the HMG would have the "Medium Armor Penetration" label. All the med pen weapons kinda suck, and I'd put the HMG in the same category. The armor pen gives them better effect on certain targets (like the HMG can chew through the front shield of a walker) but you give up a bunch of damage on lighter armored targets. It drops the damage per round below breakpoints for a lot of targets, and the targets it does work on can be better dealt with in other ways. I'm sure you could make the HMG work in some really narrow situations, e.g. Fortified armor, fully prone, and enemies funneled into a chokepoint. But outside that really narrow scope? Yuck.

The Quasar on the other hand is S-tier IMO, especially vs. bots. It is dead easy to keep the aimpoint on a bot dropship engine while the laser spools up. We ran a bunch of Quasars in our group tonight and I've never seen so much dropship carnage. The Quasar doesn't take up a backpack slot, so you can run Personal Shield to save yourself some chip damage. If you've got multiple Quasars in the group and you're on comms, you can time two Quasar shots to a turret's weakpoint to take it out before it starts rotating toward you. It recharges while it's on your back so you can displace, shoot your primary, chuck a grenade, whatever. For my money it's better than the RR, because you don't need to rely on a team reload or root yourself for 5 seconds for a solo reload, and it's better than the EAT because the Quasar is ready to go when you need it, no need to wait for call-in. The spin-up time is a downside, but you can spool up the shot in cover and shoulder-peak just before it goes off. Heat can also be a downside, hot planets will increase the cooldown to the point where the RR or EAT might be better. But on temperate planets it's great, and on cold planets it'll be downright ridiculous.