Favorite underrated/underpowered weapons?

What are some weapons that most people don't use, yet you enjoy a lot?

For me, it would have to be the 205 Brecci. I thought I was gonna hate it at first, but somehow it grew on me. Yeah sure, it can't get a OHK at point-blank, yadda yadda. But it's 2HK range is pretty long for a shotgun, plus the hipfire is really good with a Laser Sight. Just try to stay away from super close ranges, and you'll be fine.