I never turn my CM off period. No reason too that I can see. When calibrating it requires several times thru the sequence. You'll know you're there when it calibrates quickly. I use ferrite clips on the power supply and regularly spray the room with static guard.
Mods to the unit are basic reprogramming and inserting a section of straw about an 1-1/2" long all the way back to the feed slot under the dispenser. This cuts the feed rate roughly in half. It prevents the tube from filling so much. This is why the CM often drops big lumps of powder goofing up an otherwise good weight.
Several maps are available that detail adjustments to the dispensing program. It's incredibly simple to do and you'll easily modify it to work best for your needs. I still weigh 1/10th under and trickle in the 3-4 kernels to top it off. Be patient and wait a couple seconds for the scale to catch up to each kernel for best accuracy.
Pay close attention to the pan weight when lifting it empty before the start of each session. Mine reads 142.8 grs. I also watch how quickly it returns to zero when replacing the pan. If it hangs on to a tenth or two before settling just lift and replace until it settles. I know that all sounds like a lot but it takes a minute or two to do before beginning each session. I check against my beam scale and I have found surprising consistency. Don't fool yourself about a beam scale though, they require maintenance and tinkering to keep them spot on too.
As an aside I'm not sold on the advantages of weighing to the kernel. I only bother until my load is set. That load will shoot well with a variance of +/- 1/2 grain or more.
