Well I don't own a 350 but I do have 2 B28's and a Ruger Air Mag. Clones of the 350. My .177 B28 has a Vortek softkit in it and it is a great shooter, very easy to control, very solid and nice looking gun too. My other 2 have the full strength Vortek kits in them and they shoot very hard but are easy to control as well. I shoot my B28 low power more than any of my other guns. I get 975 FPS with it at high altitude. The RAM gets 1020 fps both using the CPL 7.9 grain pellets.
That some speed in a compact. Glad they are all up and running and everything was successful. I understand the need to tinker im always building and adjusting something. Good to know what the soft kit does and how it works out. And whered you get your spare barrel? Does it already have a breech block on it or do you have the know how to change one out?