I picked up a lightly used (purchased late Jan 2019) 2018 11" iPad pro last week. The guy I purchased it from said he had no problems with Beta iPadOS on it but I'm still unsure about making that jump. I did the beta thing years ago on one of my iPhones and hardly any of the apps worked correctly. It was so frustrating.
At the same time, this iPad isn't replacing a previous iPad, so I'm learning iOS12 for iPad and then I'm going to have to learn iPadOS in the fall. Oh well, it was too good of a deal to pass up and I'm sure I'll make due.