I've got 2 ea. 120 ax now and I had another one, so I have owned 3 of the 120 AX. The first one started acting up after 1.5 years, I put after run oil in it religiously but Tower said I abused it and refused to fix it under warranty. I still love the engine, since I bought 2 more, but be prepared if something goes under warranty not to have it fixed under warranty, even if you put after run oil in it and run the fuel out, etc.

That was a typo earlier, it has a 15x8 prop on the new 120 AX, I see no reason to add a pump, the 120 AX is a beast on the Venus II, unlimited vertical it can even do knife edge loops easily.