the 194.5hp is the power at the wheels(what the dyno measures), 225hp is what is measured at the crankshaft. there is a loss of power through the transmission.
The zhp is actually quite a bit faster, not because of the 10hp, but because of the differential. 0-100km/h for the zhp is 5.7, 0-100km/h for the regular 330 is 6.1 (both manuals)
i would go with the 330i with sport +premium packages(or the ZHP