Oilspot,

You don't mention what type of tow vehicle.   This doesn't matter a whole lot other than the mounting position may be at such an angle that some controllers may not work for your vehicle.

I use a Tekonsha Envoy in my current truck (Excursion) -- the Envoy can handle the steep mounting angle on my dash.  Works just fine.

If you're vehicle doesn't have a "factory trailer tow" wiring option, you may want to plan your wiring first.   My old F250 needed an extra diode under the dash, a constant source of problems.  The brake controller in that truck tapped into the brake light wire.  The only problem was the emergency flashers also fed that same wire.  The diode solved the problem of going (slowly) up a hill with the flashers on, causing the controller to pulse the brakes on the trailer (adding insult to injury).

Newer vehicles seem to have this issue sorted out, or at least my X does.   (Heck, all the wires were conveniently labeled under the dash by the factory!).