I bought a chrony F1 about 15 years ago. It was and still is my first chronograph.
On an overcast day it seems to work pretty well and consistent. Sunny days and especially sunny days with snow on the ground it seems to have readings that are less consistent, and some missed shots.
I always set it up 30 feet in front of the muzzle.
Overall it has served my basic needs for working up loads rifle and handgun loads, and fiddling with rimfire velocity checks.
If I ever upgrade I'll go with one of these strap-on bayonet style Magnetospeed chronos that do not rely on light at all, and don't need a tripod or any 'lining up'.
