That's a rather broad statement. I was consistently getting +/- .2 error on my old CM as verified by my FX. As the CM got older, the errors got worse. It wasn't user error. I bought a second CM to speed things up, and it too would drift. Meaning, the scale would show 43.0 and the FX would confirm it was a tenth either way. It's just the nature of the beast with a load cell scale. It's essentially a variable resistor. Apply a load, resistance changes, measure voltage output, divide by 1024 and you get your result. Temperature, static, voltage variations both at the wall and out of the transformer all make life hard for a load cell.
I'm sure the CM is great for 98% of the reloaders on this forum. Some of us require more accuracy and consistency. Yes it's a $1000 to go with a V3. It's at least a $1000 to fly to just a single two-day match. If you are in the aforementioned group, you're crazy to not show up with the best ammo you can make.
I switched to a V3 and AMP annealed brass at the same time. Coincidentally, I laid down the best groups from that barrel right after the switch. Finally got those elusive single digit SD's and an ES of 12. I still keep a CM under my bench in case of emergencies, but I know that I will have to temper my expectations.
If you guys got good CM's, I applaud you. There are a lot of us that can't share in your success.