That looks awesome, can't wait to see some vids! My only concern about building my twin KMB 28 powered PX16 is what's gonna happen when one jet gets a gob full of air and loses thrust. Just for a laugh I tried the PX16 stock and like nearly all NQD stuff it had 'vector steering'. Being a cat with that wide stance when you shut one motor off it really cranks a hard turn.When you trial it find the flattest piece of water you can and maybe start with the weight well back to keep the intakes firmly planted. I can imagine an impromptu pirouette being less than pretty
(FYI, you won't get 12v going to the receiver and servo as the + and - are in parallel not in series in an ESC y-cable, the reason you need to disconnect the + lead on one of the ESCs is because it can damage the BEC circuits on the ESCs.)