Engines dead stick for 1 of 3 reasons, lack of air, gas, or spark. No one can blame an engine for dieing in a hover, they only have themselfs to blame for not properly tuning or not properly cooling, or not having enough gas.
The inverted issue is easily fixed, they do have a rough midrange but I have heard DLs with the same issues.. we have several at our field. I have seen DA 50s with the inverted issues and then I have seen them run like a charm. Most of the time you can fix it with the atmospheric preasure line though.
In the videos I posted of the AW 300 it had a DA 50 in it with lots of inverted and hovering, no problems here
That being said the DA 100 is a completely different animal, rare to have any issues at all with them.