This might seem like a strange question, but I'm always left wondering when I've done enough/too much with my fingers. I usually stop when performance begins to noticeably decline, but they don't usually feel too tired or sore. I try to train basically just based off how my body feels, so I was wondering if y'all had any guidelines for your fingers?
Its good that your fingers are not sore or in pain, but mine feel pretty tired after a full HB workout. I've been using the 7s on and 3s off for 6-7 sets with different weights and have noticed visible improvement. Check out the Rock Climbers Training Manual for detailed instruction. Also keep track of which grips including sets and weights to keep track of progress.
I've heard it described as getting a car door slammed on your hands...haha. I'll usually feel pretty pumped in my forearms. Fingers might get a little swollen, but usually not as bad as actual climbing or bouldering.