My experience after about a year isn’t as bad as yours, but it isn’t as good as I hoped it would be. I don’t have solar - so only two CTs. Total consumption is very accurate - after they recalibrated my unit to compensate for an error during manufacturing.
Sense has picked up about 25 devices. Motors are very accurate - it picked up both vacuum cleaners, leaf vac, electric chainsaw, old & new garbage disposals, garage door opener, both fridges, my old washing machine, and my paper shredder - these devices were identified very rapidly. And have stayed mostly accurate.
After almost a year, it just picked up my air handler blower, which comes on for 5 minutes every hour (ecobee3 scheduled). It also picks up my outside AC unit (discovered several months ago).
For my old microwave, it picked up the appliance light and the magnetron. For the new microwave after several months, it has only picked up the magnetron.
It has picked up the halogen lights in the master bathroom (~600W), the LED lights in the downstairs guest bathroom (~30W), and the lights inside my kitchen fridge (although as of this week, it has started calling something else the kitchen fridge lights).
My luck with heating devices has been up & down. It picked both elements in the electric dryer, and then forgot one of them. After a few months, it picked it up again - so I’ve grouped both elements now. It picked up the small element in the stove, but sometimes calls it the dryer. It picked up my Keurig coffee maker.
No major electronics yet. There is an unknown device that comes on for exactly 4 seconds and consumes 100W when I turn on 4K TV in my living room. But it hasn’t picked up the small TV in my bedroom, which is used much more often.