My Father in Law only uses the Field Pros and has for years. Not sure what he likes about them but he is the type of guy that won't put up with crap and change if he felt he was getting a chitty product.
I stopped by Field Pro on my way home yesterday, and the guys are super nice and helpful. I ended up trading in 6 broken units for 6 new “refurbs” and picking up a unit my uncle with dementia left there for repair a couple years ago. Hopefully, I’ve now got a several year supply of feeder units.