I decided to go with the new Magnum xls 52a 2-stroke. I figured if I wasn't satisfied with a sport 42 than a high performance 30 sized 2-stroke didn't make much sense. And as far pure power goes, the 50 4-strokes aren't that much stronger either (at least not enough for me). And I thought about the BB 46's and thought that seemed a good fit for the overpowering effect that I am going for. But then I saw that the Magnum 52 was only about 1oz heavier and a lot more powerful. It also seems to have mostly positive feedback from the users at RCU. You can also get it with a free glow starter w/charger, 2 thunderbolt glow plugs, a four way wrench and a crank fuel pump. That seems like a good deal to me. And I am makeing up for the added weigh by using micro and mini equipment. And I am going to use a GP 12oz tank as someone on this post stated could be done. This plane seems to be very solid and strong so I don't think any extra reiforcement is necessary. Especially if I use most of the power for vertical and not for all out speed. We will see. I will let you guys know how it works out. Let me know if you have any suggestions or comments. Eric.