@Phil
An R&L tournament requires the AWSA approved prop.
Factory prop is 13.25 x14.5 4 blade OJ and this 5.7L has plenty of power. This is a pic of my 2014 ProStar going down the assembly line.
MC does test every boat they make. MC has a slalom course on the lake to check Zero off as well as run it through its paces using the customers prop.
They sometimes remove the customers prop for transport so it doesn't get bent or stolen. The dealers then put it back on. There is a chance the dealer received several different boats on their shipment from MC and somehow mixed them up. If the boat was used at a Boat Show, often all the running gear is removed so the boats can be lower while on display, a mix up on the prop could result.
I can tell you from first hand experience, the MC factory workers take tremendous pride in their work and the boat is Q.C.'d at every assembly station before it is released to move down the line.