fanboy alert....?
What matters is user satisfaction in the end.
And numbers on paper don't have to reflect that in real world...
I have been on a preorder list for x45 for 4 months then quit and got new k45 in 2 days from store for same money.
My pick was firstly based on diesel fuel but later it turned out that x45 does not prefer diesel so I would fly it with kero(petrolleum) like I do k45.
(Over 90 liters in 6 months, so I did fly it a lot)
also there are few reports of x45 shutting down due to pressure/temp sensor and they were sent back and fort to Spain where they work and back in Germany they dont. Look here on forum.
Both engines work for most users and people fly the crap out of them when all is ok. That is ok.
You already have an k45, right?
hope you will maiden that viper soon and then you will have some real world data and fun