Where are you looking for heating? Check out Jehmco. Their titanium heaters are great and they come with top-quality Ranco controllers, which are industrial use. A 1000w rod and controller goes for $150. Each controller can handle 1800w, so you could run 1000w + 500w rods on one controller.
Best to run multiple controllers if you can afford it. That way, if a rod goes out you could easily tell. If you have more than one on one controller, it will difficult to know if one's gone out.
http://jehmco.com/html/heaters.html
P.S. I have a Ranco controller and a 500w on my 57g planted tank, talk about overkill lol! Left over from the 400g, so why not put it to use. Being that the tank is indoors, the heater kicks on, then back off a few minutes later. With 500w, it's super easy to keep the temps spot on