I have an R-com 20 pro and have not had great hatch rates from it but nothing to compare to so it could be the eggs, I have ducks as well so not sure how they compare in terms of ease of hatch. First hatch got 3 from 7 fertile eggs, 10 0f 13 on the second time but had to help quite a few out and had problems with the humidity not going high enough at hatch time. Would be happy if that hatch level all the time but hardly stress free having to check and tinker all the time with little bowls of water. Know that others have had problems too. They are expensive and there are probably cheaper, more reliable models.
On the plus side very easy to set up and run. Easy to clean. Loads of different automatic settings plus a manual mode. No fiddly parts.