I agree the gpx 125 is the way to go compared to other china 125 motors. It's like comparing chalk and cheese a few guys down here have them and love them compared to the old china 125 motors they had before.
here it is, they say it is a ZS engine which is correct it is a ZONGSHEN engine, but this is the gpx it just doesnt say that, this engine is awesome and for a 125 you will be beating some larger capacity engines on the dirt.