It's just another AGM, but I had to laugh at its "More Power than a 100 Farad Capacitor". Der!
But be warned, apparently smaller caps will melt HC800s etc! (I've borroed that one from someone else's jest about misapplied specs.)
And please be wary when paralleling batteries - especially AGMs.
As to extra batteries, although unlike audio systems you may not worry if the alternator cannot keep up, keep in mind a bigger battery merely extends reserve time, and they still need to be recharged. (And AGMs do NOT like remaining discharged.)
UPDATE: I removed the former opening line "I just got a notification for this thread for reason unknown (subsequently deleted perhaps?), but I checked out that HC800 battery".
The reason is now known.
Some git changed my displayed order for reverse chronological. It's a great feature - provided one remembers to go to top of page 1, not bottom of (last) page 3!!