I'm pretty pi$$ed off at Apple for this. There was absolutely ZERO warning that converting to APFS would cause performance issues with older machines. Their whole promise of substantially improving performance was utter BS. I have a mid-2014 13" MacBook Pro that has been sluggish and stuttery ever since upgrading. Super slow booting, agonizingly slow user switching, freezing cursor in Safari, spinning wheel, slow app launches, slow waking up. it's incredibly frustrating. What I'd like to know is, is there any way I can downgrade back to HFS+ and still be able to use my Time Machine back up, or is that pretty much useless now? I don't mind having to erase if I can use the backup, but I don't want to lose everything I've backed up such as installed applications, system settings, etc. There actually is a slight chance I haven't actually backed up since installing High Sierra, in which case I can just erase the drive and reinstall from the Time Machine back up, correct? I was really hoping to upgrade the SSD to a larger capacity, but from what I've read, that's a huge PITA and quite costly. Any help is appreciated.