I have the same boat, also in black and just hit 12 hours too. This is my first jet boat, but long time boater. I haven't had too many issues adjusting to the jet but having now docked and loaded the boat a handful of times, I think I may invest in one of the aftermarket options to improve reverse and slow speed control. I had the Stoltz roller put on at delivery, well worth it so far.
The hole shot power and response is impressive, it gets a 225 lb. guy out of the water on skis instantly. It does throw a lot of spray on tubers, I extended rope with a 10' extension that dramatically improved it. I see you hit almost 52 mph which is great. I've only been able to hit 44 mph so far but limited opportunities to get WOT for extended stretch of water. I didn't feel like it had a lot left though, so I'll have to check that out.
Couple of the early issues I've had, mostly minor.
-Both captain chairs had the underneath mounting bolts spin out while on the water. I'll probably use some loctite on them when I get a chance.
-2 of the side rear sound dampening foam sheets have peeled off the sidewall (way in back where it is really hard to reach). I'll probably try to get the dealer to climb in there, my body doesn't twist like that anymore.
-House battery doesn't charge from engine in standalone mode, only starting battery charges. I had to put in the emergency parallel mode to get both batteries charging from the engine. If I am understanding the user manual correctly, this isn't how it should be. It's going in for the 10hr oil change so I'll have that checked. Mine came with Interstate batteries.
-I had the Yamaha Slampak tower speakers/amp installed by dealer at pickup. They sound great, but I'm not thrilled with zone control between boat speakers and tower. The boat speakers are barely putting out anything at the point the tower gets overwhelming. Also have had a few hiccups between Connext screen and rear fusion deck becoming unresponsive communicating with eachother on volume control. Also realized I will need a sub. I'm not the guy blaring music for the whole sandbar, but definitely lacks low end with the tower.
Love the layout, space/storage, and performance so far. Lots of compliments on the water. Feels awesome to have one of the nicest boats on the water vs. The same old bow rider that everyone else is running.