ThermoPop would be the best option. Its faster, the display rotates, is backlit, and has a longer probe. With a Longer probe length your hand will stay farther away from the grill and you can work with the bigger thicker meats. In my opinion I really don't see the other device as a competitor to the Pop. I think Shagdogs posts really helps find the difference in the speed.*
One other point that I don't think anyone has mentioned is the service that ThermoWorks provide. They do it right by providing great service to backup their awesome products.*