... especially in combination with a magazine that you can load on the fly (RSCB, Hopper or turret). The special sauce is: you never have down time loading mags or pumping your blaster, you're just always shooting. You can't just think about the pace of play when shooting - it also matters how much time you're spending futzing around loading mags. With ... an RSCB and a flap valve, I'm rocking and rolling 100% of the time. It's great.
This is so understated in the hobby today. A frontloader or RSCB/hopper (or the new Commandfire Hopper) can be loaded with a handful of darts whenever you've got it and a few seconds to spare. Mags take time to unpack from your rig and load, then need to be loaded into the blaster. Sure, you get a burst of up to 20 DPS as quickly as you can load your mags; but once they're out? You'll be out-of-action loading somewhere for several minutes at best. I found that a single shot blaster was my best bet last PvP respawn game because of this.
I'd also like to make a few light turret-style reload flywheel blasters, to bump them up into the #scavenger master race.
Mags work great for HvZ, from what I understand; as it's PvE elimination and you can safely spend an hour or more reloading between engagements in exchange for really high burst actions. In PvP wars, mags just bog everybody down (unless they bring enough to be able to dump the spent ones and pick up fresh loaded ones between rounds, which is unusual, but also something that the mk13 was good at).