912ULS, or 912IS or?

[Hawkertech]

I am pretty sure I am going 912ULS, for some simplicity in maintenance, and cost. The only thing that concerns me is the chance for carb Ice, but what I have been reading it is not very prevalent in these engines.

[Okent]

I have a Flight Design CTLS with a 912ULS. Works just fine and no complaints.
However, I'm building an S7 SS and will be putting in a 915iS, Airmaster prop.
There is no substitute for power, the fuel injection is simplicity and it has the Rotax warranty.
Sure, there may be some teething pains but Rotax has been pretty darn good about backing up their product.(from my A&P who is the guy for Rotax in my area)
It is more money for the fuel injection and larger engine but I just know that if I didn't use that engine I would always regret it.