AGM or Lead-Acid?

I cleaned connection points and unplugged/reconnected. Now the maximum voltage at high RPM is 14.6V
I do have a Battery Maintainer that auto identifies it as AGM. it backs off at 13.1V to a very small current.
I will watch it a while and then get another AGM.
Googling Battery Reviews is a joke. I think they are funded by the Mfr. No two reviews seem to agree on a Brand.
I do prefer to buy where I can get access for a warranty exchange if away from home.