To put that into perspective, even the Excalibastard crits for about 20K at that level range. At level 40 upwards, its roid damage hits for 40K easily.
Best of all, it's a quest reward, meaning that there's no farming involved.
This will absolutely chew right through bosses, up to and including the final boss. While it has very high recoil, it comes with a large magazine, slick reload time, is non-elemental, and gets a damage bonus for using the stream continuously.
If you want to snap the game clean in half with them, slap one in the hands of Wilhelm with a Blaster class mod, a full five points in Laser Focus and one in Laser Guided. With the only drawback being recoil, they pretty much fuck up whatever you point it at with astounding quickness.