Caldwell or fx chrony

Which one is better between Caldwell Ballistic Chronograph and Fx wireless chronograph?
Can i shoot through Caldwell while making groups at 30 , 50 or 100 yards ? I mean aiming for targets and measuring FPS at the same time.. is it possible??
It doesn't matter how far you are, you will still be able to get readings off either chronograph. The only "con" to the caldwell si that you will have to grab more gear to set it up at a farther range and you have a smaller window to aim at.