The first difference between the Ovation 56 Eco and the Rcom 50 Max and Pro is the egg capacity. The Ovation 56 holds more eggs; up to 56 hen-sized eggs or equivalent. The Rcom 50 Max and Pro models can hold up to 50 hen-sized eggs, or equivalent.
The other difference is the that both the Rcom 50 Max and Pro have a humidity display and automatic humidity control, whereas the Ovation 56 Eco does not. Finally, the Rcom 50 Pro has a ‘species selector’ feature and specific settings for egg-turning; both of which are unavailable on the Ovation 56 Eco.