I've sat behind various versions of the Rotax 912. Whilst the iS is a technological step forward, I'm not sure it is true to the relative simplicity of the 912 design and do you really need to sip even less fuel than can be achieved by the carb version? Personally, I think the best engine is the plain old 912 as it runs more smoothly than the 912S. I would go for this one unless you feel that you need the extra 20 or so horses.

Rotax replaced some fuel pumps and we replaced some filters but later there are no complains registered is the reply from Pipistrel. There are now over 60 912iS Pipistrel flying.........

Flight Design offer both the Carb & injected versions on the CTLS range. In the USA since the arrival of the injected version I think that has been the only option chosen.

If you take a browse around Flight Design CTSW CTLS CTLSi C4 Forum you'll find plenty of discussion there. Warning!!! Ignore any posts there from a guy called 100hamburgers - he's a ******** (I think it's obligatory for all forums to have at least one!)

FWIW I am very happy with the carburetted version in my CTLS ~ 450 hours now from new and still purring along. The weight penalty and extra complication (needs fuel header tank etc) seem too great for the gains claimed.

What Shoestring Flyer said.

Operated my 912uls for the last 9 years with zero issues. You will use 18.5lph.

Rod1

D-Motor promises to be the future for small light aircraft. It's a marriage of very old and modern technologies to produce plenty of power, while being light and economical. It will fit directly into frames designed for Jabiru engines, occupying less space inside the cowls due to the absence of overhead valve gear. Also becoming available as a 6 cylinder. https://www.youtube.com/watch?v=wxK_GcZ3RSQ

912is
 

I built own and operate a Sportcruiser with a 912uls and gave also just finished a Bristell with a 912is.
I think the remarks made that the ULS is a lot simpler are very true and cheaper if you do the usual low annual flying if mist users. There is a lot to be said for the ULS and I don't think you would be disappointed, It's by far and away the mist used 4 stroke out there, and I firmly believe in following the herd. We deliberately aimed for a very top speck aircraft with the Bristell with Twin Garmin Glass and autopilot, we chose the IS to match. So far we have only ground run it and it's smoother than the ULS. Rotax staff have told me it actually produces 105 horse but we will see. So far we are very happy with it but it's very early days. Having done both now the IS is a lot more complicated to install and we needed professional help, I would happily do a ULS myself. I use Gary Masters (air masters) and I give him our Sportcruiser every year for an annual as I like someone else to look at it. So the maintenance costs to us aren't that different. Give me a call if you want to look at both engines, I would suggest with less experience and fir a lot of people's flying the ULS is the best start.
Pete 07976262833

... as so many have promised ...
Not that I believe my countrymen's work to be poor, nor the resulting offer (=product+price+service). But I'd prefer to see the promise proven.