I use several guns myself.
My favorite sniping gun is the Tiberius 9. It is my favorite gun to pull off single shot head shots with. However this gun is a heap of trouble when you have a barrel break. As much as I love it, sometimes I wonder if the juice is worth the squeeze.
My more reliable guns are the BT combat 4's when I want to rough house it a bit and take a million shots in terminator road or crawl in dirt and mud.
I know they are only 150 dollar guns but they have served me so well that I prefer playing with these better than the tiberius.