I changed my mind, I went with a few peoples recommendations and bought the UCD60. I was recommended (by the owner of the model shop) that an OS FX 90 (2 Stroke) would go well in the model but I really wanted to use a 4 stroke engine for the first time.

In order to get comparable power to the OS FX90 (2 Stroke) would I have to go as big as an FS 120 SURPASS Mk.lll (4 stroke) or would a FS 90 Four stroke suffice?

The difference in weight between the OSFX90 (550gms) and the FS 120 SURPASS Mk.lll (920gms) is 370 grams. Would this make much difference?

Thanks.