It isn't all that great in PvE. I used it last night for a few hours (just to show off I had it, not going to lie). It is better than Coldheart for killing the random adds but for something like Calus the Coldheart was still better. I thought the heat wave might pick up additional damage nodes and hit like a continual exploding round but I didn't see that happening (unless the numbers are hidden). If it really is just a bug, fixing that is hopefully enough. A nerf on the PvE side would actually make this gun garbage.