With my eyes changing constantly and my preference for the scubapro frameless mask I have found the best readers, for me, are the cheapish plastics stick ones from amazon work best, surface prep being the most important step followed by letting them dry in place for a few days a close second.
I have tried the glass ones, like trident sells, which are better lenses but the glue they supply is useless and washes out far to easily, I had turned to glueing them in with silicone which makes them permanent so they best be in the right spot and the right power because there is no going back.
The plastic ones have held up very well, I dive a lot and they hold up for rinsing etc and those times when your mask just doesn’t want you to enjoy your dive and keeps on flooding. I wouldn’t trust them for long term spare mask use, I use one of my old silicone glass one for that.