Their useless imo, you need the case for it which is a cheap feeling plastic case on the outerside. So if you have a case, you'll have to remove it each time, put on the charging case, and either use the cheap charger case, or remove it each time from charging and put your case back on. That would annoy the heck out of me.
The whole "wireless" charging is just gimmick marketing. Now if you could just drop any phone on the mat as-is and charge, then we'd have something to talk about, maybe in upcoming years lol.