Apparently amanresorts are no longer recommending Trans Nusa flights, which make a 20-minute stop in Lombok on the way to Sumbawa, because the service has been found unreliable. Flights would get delayed or cancelled with little explanation or recourse, and guests wound up missing international connections at DPS. (Perhaps this is what FlyerEC was alluding to.) It is still an option, though.

I suppose one could book the floatplane when connections are important and the Trans Nusa routing when they're not as important. As long as one could deal with the baggage limitation o/w, of course.