Has anyone actually used, or try to use one of these new ebay AP labels? And if so, was it a positive outcome?

It's no error, it's profiteering. 

By under cutting external AP pricing they're forcing sellers to either take a loss on calculated post or buy post through eBay. They more sellers they con into using their post, the more profit they make. They would be getting extremely low trade pricing from AP because of the shear volume of post they buy, significantly less than the 'discount' they are giving sellers, therefore increasing their profits. Currently changing all my items to flat rate post, I'll be sticking to external purchasing of labels and my own AP business discount. Ebay makes enough profit off me already.

so I asked ebay again, is this offer for the sellers or the buyers? It is about for purchasing auspost postage labels from ebay for a discounted price and yes its for the sellers...so if this the thing why would you fiddle with the perfectly working postage calculator in your system..i spent hours on the phone explaining and telling them they messed up their system, they already were offering discounted postage so it only could be done to change the discounted postage percentage on the ebay label purchase page..that's all. Now they are misleading as showing 80gr item's postage cost is 15.25 (which is $9.70 at the Auspost counter) a 44% of savings 🤣🤣 wow!  On top of it, buyer paid $8.54 for postage which exactly eBay's offer to me to purchase label from them. "$0" savings minus fvf fees. No thank you eBay I will stick to my auspost business postage rates.