eBay is not recommending them they are offering them as a service for the seller to use them as a preference if they wish.
It truly depends on the Evri delivery person in your area. We have a fabulous Evri lady, always on time, polite, and sends me several tracking details to show the progress of my item.
Simple Delivery may be coming in as mandatory for Private sellers, and there the buyer selects the postal service they wish to use.
Currently, just check out the seller's postal service choice on their listing, before buying.
@sarah271