I built a 4 * 40 as my second plane and powered it with an OS .46LA (not the best engine). After I became comfortable with it, I made some modifications, and in a sense, it became my third plane too. I replaced the engine with an OS .50SX, removed 1 bay from each wingtip, and increased the throws. Now it's a lot faster and aerobatic. I will agree with the others that it really floats on landing, especially with the full length wing. Overall, I am really happy with my 4 *.
I have a warbird in building right now. Before flying it, I plan on adding weight to my 4 *. I may need to beef up the landing gear when I do.

Scott