"ajshoots" I prefer the Competition Electronics Pro Chrono with IR screens. Has been by far the most reliable and with the IR screens, I have had absolutely zero errors!! I have used other products made by CE and they are a great company in all regards and make a great product.
Okay I can't find any reference on the CE Pro Chrono site that speaks of "IR Screens" . Could you put up a link. I have the Pro Chono and it is quite light picky. The diffusers are useless unless the light is directly above. It does work though under the right conditions. I shot mine all apart one day, (who hasn't?) they sent me another for 70 something bucks.