Tower, GMS and Magnum, my 3 favorite engines. My Tower .46 is in a sea plane because it never quits out on the lake. I bought 1 Magnum .52 and liked it so much I bought another. Then I bought a 4-stroke, a .61 on sale, then 2 more, a .91 and a .70. I swear the Mag .91 runs as good as my Saitos. Don't even mention a .91 2-stroke. I sold my OS FX and have a Mag .91XLS. My GMS .47 is in my regular flying 3D plane and my OS AX is waiting another kit.