We've had a hydraulic push now for 25+ years. That aspect of it has never ever given any trouble and I don't expect it ever will based on the way this one is built.
If I was looking for a new spreader today tho... very likely be a Hagedorn with vertical axis beaters. Just keep in mind that you need some serious power in front of it.
Regardless, it would be hydraulic push. I do not want to see an apron chain spreader, ever again.