I've never owned a brake controller. After researching I decided I wanted a Tekonsha P3 controller as it received great reviews, is progressive and can control electric and electric over hydraulic brakes. The only issue, I didn't really want to spend $130+.
I kept a watch on eBay for a used one and ended up finding one for $35 used. When it got here I was disappointed to find the manual lever was broken which was not mentioned in the ad. I contacted Tekonsha with the details and to see if they would send me a lever as it is just held in place with a torx screw. They said even though I wasn't the original owner the controller has a lifetime warranty and they would replace the whole unit.
Tekonsha contacted a dealer near me, Camper World, to let them know I would be coming by. Went by this morning and they handed me a full retail packaged brand new Tekonsha P3 controller in exchange for my controller.
THAT is customer service. Very impressed.