That sounds about right, the new 1.8 models have identical pitch impellers which is not ideal but okay. Because the STBD side loads a bit more efficiently due to the direction of impellers’ rotation it lowers the RPM on top, 200 sounds about right.
if it drives you nuts, you have two options:
1. tweak the pitch on the trailing edge, probably just one of the two - 7,700 in cold weather will be less in summer heat, so perhaps de-pitching the STBD side - there are threads on how to do that.
2. BETTER option IMO - purchase
@Ridesteady and don’t look back! Twins humming along in perfect harmony at any RPM level.