Another cheaper option is G10 or FR4. I've got copper backed FR4 on my list of things to try. Apparently it has a more even heating due to he copper against the heated bed. I've been using the glass held on with Binder clips until recently when a few binders popped off and tossed the whole lot on the floor of my garage sending shards everywhere.
Couple things that comes off my head that caused my “adhesion problems” over past years were incorrect Z=0 height, uneven bed, rigidity issue on moving bed, and worn out nozzle. Worn out nozzle is easy to spot, if your extruded material curls up before dropping down, that nozzle is done.
It had been more often an excessive or uneven force forcing print to depart from bed, than print simply detaching for lack of reasonable adhesion.
Also, a last-resort workaround is to put the model in the air so first 5mm(1/4”) or more is just supports. Support material is more tolerant and top of it is naturally more flat and parallel. Downside is that the bottom of the print looks just bad.
Anyway, a heated bed is much more impactful than the bed surface. Glass at 60°C alone is enough for PLA (with glue it adheres too well and stops working again), while you will need both a heated bed and surface covering for ABS.
Also, any PVA based glue works. If you dissolve some white glue and spread it through the glass, it works even better than solid glue, but it's much more work.