Very valid question and fair.
I wasnt referring in general to the JP S3 when I made my statement. I was just stating in general that I would rather have a lower HP engine using all the rev band than a higher HP engine using only a part of it.
The JP engines are quick if you are lucky to get one with a good carb. I have seen 6 so far and only 1 of them really shifts. But in saying that I have no problems staying with it with my RB 3-port producing 1.25+HP.
Its all in the tuning and driveability of the engine. The RB has a good power deliverance over the whole range which allows it to be competitive still with some of the bigger engines.
In all honesty I really believe most of the high prices on engines are false marketing. Like Microsoft, Virgin, Sony etc.... you are just paying for a famous brand name yet with some of the big name companies (Reebok, Hitatchi, etc) the name is big but the products are C***. Same thing with this hobby. Collari is a big name but his engines are C*** to be totally honest. Our local dealer actually gave away 6 of them free to get rid. JP has always been a big name and always produced fast engines (I own a JP Rex .21 Turbo) but the .12's seem to be temperamental through poor choice of material on the carb he makes.