Niner,
I do agree that telecom are a specialized subset of AGM.
I do use a large inverter with my telecom jars. But then 556 amp-hours from four batteries vs a 160 amp draw is only 40 amps per cell. I have by accident done 276 amps for a few moments, with apparently no ill effects.
I now limit charging to 27 amps per cell, because they quite happily overloaded the Magnum inverter/charger (125 amps max, and they MEAN IT, 127 amps overloaded the unit).
I admit I don't miss checking electrolyte levels one little bit.