I have one that works very nice. I did have to have one of the screens replaced years ago. It works with spacings from 2 to 8 feet. Has nice big numbers. Connects to your PC to upload data to Excel or any program capable of reading it. It also stores shot strings basically forever, for recall on the unit. So, you don't have to have your pc connected to use the functions, but iirc, that is the only way you can print the stuff out.
I did have to add the infrared sky screnes to get 100% reliability but that is probally due to my range being shaded, It never misses a shot now. I do have a permant stand that I place it on, making it eaiser to line up. I use a lazer in the bbl to make sure that its centered between the screnes and ALWAYS take it out before shooting. Good luck