It's early in the test but i have been watching the temps and we finally go sun with calm to low winds for awhile and with calm wind the standard shield was up to 1 degree warmer than the fars and the pro was even with it but as soon as we got a little wind the temps when down on both, the pro down .5 and the standard down about the same. I decided to compare the two shields to each other and generally the pro runs about 1 degree lower than the standard. It looks like the extra black louvers inside the pro is the big difference. Keeping in mind the possible variations between the sensors as long as there is some wind the standard does a good job against the fars and for the price isn't bad. For those that want the most accurate it looks like the pro is the way to go. Right now wind 4 mph pro is .4 lower and standard is .4 higher. The thing is with the fars my dp always seemed to run high and now it is doing fine. Oh yes, i plugged the hole in the tube, the cable was flopping around in the wind so used some foam rubber and plugged it. Now cable is more secure.