I was a big fan of Nelson stuff for a long time. The simplicity of adjusting the rotors was one reason why. Lately I have noticed I have more Nelson failures than anything. I also installed a lot of their controllers, and I have had to replace alot of them
The outdoor boxes have a real problem with moisture and the indoor one have problem with heat. Its a hard sell on a new controller when the one you installed last just goes bad after the warranty is over. This makes ya look bad for choosing an inferior product. I have installed more than one replacement without making a dime, just to keep the customer happy.