Yup, I absolutely hate it and my account was only switched over to compulsory SD two days ago.
I was charged for a label that I didn't even create because a buyer purchased two of my items so naturally I wanted to post them together.  When I added tracking details for the second item (and that was a faf as there's nowhere to do this now. I had to have CS send me a link) a charge for the label was placed on my account. I've been told it will be cancelled and refunded automatically so I will be keeping a close eye on it!
All of my active listings were switched to SD and a buyer from Sweden was unable to check out when he purchased one of those. I had to cancel the item and create a new listing.

The same item had a small parcel label created when it was actually a medium parcel. Fortunately the lady at the Post Office let it go. She acknowleged the many issues with this ridiculous system from Ebay.
It's totally inflexible and it's definitely not working correctly.
I can easily use Facebook Marketplace instead and I really don't need the hassle so I'm afraid unless something changes then this is what I will do.