lamptron do a nice range of fan controllers.
i have a bitfenix hydra pro, its great especially if you have bitfenix fans as you can switch the leds on and off.
the 2 bay fan controllers ocuk are a bit poor tbh, they have massive screens and in my experience they just dont work properly, manual ones with twiddly dials work best and offer a large amount of wattage per channel meaning you can link a few fans to the same dial