My neighbor has a QX (quite a bit heavier) and he's getting 54-55 at WOT. He's thrilled with the performance and how quiet that motor is - he'd always previously had I/Os and the 450r is substantially better in every way (quieter, better economy, lighter, much less maintenance).
I can not imagine going over 50 on a Bennington. I can’t imagine even wanting to unless I was outrunning a storm. With that said that would be sweet. I honestly wouldn’t use the HP and I think going 35-40 is plenty fast for me. I can understand why people would want to be able to...because they can! It would be fun to experience it! No one ever said I wish I did not have extra power especially if it’s in budget!!