I voted that you should go with the O.S. Max 1.20 FS Surpass. The O.S. will have plenty of power no matter what people might otherwise claim. It's also going to be the most user-friendly four stroke on your list, so it's a good choice for a first four stroke.

If I were choosing for myself, I'd probably select the new Thunder Tiger F-130s that Ace Hobby showed at the iHobby Expo in Chicago last fall:



Thunder Tiger is usually best in class with regard to overall value and performance. It's a shame that their outstanding line of four stroke engines is too often overlooked.

Good luck and good shopping!