The RCGF engine weighs in at 825 grams with ignition, motormounts and everything. O.S. 95 is 767 grams and a 91 four stroke (the 5 mfg's I checked) ranges from around 700 grams to almost 900 with pump. Not to mention the extra weight of the mounts which puts the RCGF 15 better than some and more than others but always in the right neighborhood. As I said I am new to 3d so i didn't want to throw anyone off track, just added a suggestion for another engine option. As for it being doggy I am not sure I agree just by watching it in different planes and you tube of course. I have seen it in extra 330's both the .40 and .60as well as yaks, Sukoh's etc. The vertical climb rates always seemed very good (sometimes climing straight up and out of site) to me but keep in mind I am new at this. Other comments will be appreciated. As for personal use I am going to either use this or a webra 120 on my phoenix and probably the 120 will win and this 15 on something else after I get it tested out on my p-40. I mention this one and the webra mainly because i have them already and no-one else had mentioned a 15cc gas as an option.
As for your questions I have to leave those up to others who are not new at this and have much more experience.
Good luck and please keep us informed on how it goes....... I have much to learn and these strings help alot......

Please keep on here and don't let this thread die. It has a wealth of information that I would like to see continue for us newbies. We need the advice and stuff.