The X-Eng one os good quality, or Wizard sells an adjustable, I've used one of these and as said, you want it to be off when you are driving and come on when you've been stood for a couple of minutes. IIRC mine is set around 90 degrees on the top hose.
On blue I used a non-adjustable (sealed) one form Merlin motorsport. To adjust it just move it down the radiator untill it comes on late enough.