We have a couple of STS engines at our track and they are just as fast as the Nova based engines (how could they not be, they are copies
)
I had a STS .15 in my Impact and it was a great engine.
Also spare parts are dirt cheap AND they fit in the Nova engines.
I would buy a STS before I buy an HPI, simply because I'm sure HPI is gonna jack up the price for theirs considerably.
Sirio's can be very strong engines with a Nova carb, but they are off limits in my book because they are imported by Trinity.
If I wanted a Sirio, then from Hong Kong.
Picco engines (Ofna, Omega) can be very fast, but again they need a Nova carb. Their quality control seems to be not the best out there so make sure you check the engine before firing them up. Oh, and did I mention to stay away from the Trinity imported Piccos?
Rossi: Totally overprized piece of junk with a fancy head on it and they are imported by Trinity. Nuff said?