I'd go with the E3650 If I were you. I rebuilt my g1 bought custom guides, jm seal, and the tarantula spring. It shoots high 500's in .22 cal and in .177 it shoots high 700's It's very accurate but I just haven't been too happy with the power. I put a jm seal in my air hawk and the fps rose 50-60fps and now shoots 950-960 fps. good stuff.