It's a Super Charge model NF66H, 750 CCA, maintenance free lead acid. Price I think was $225 from a place in Devonport called Norco Batteries. They deal only in batteries, used to actually manufacture their own brand on site up till about 20 years ago. Now they just sell batteries imported from Asia. As for the Supercharge brand quality, well,............ I had one in my Skyline for 12 years. Only thing I made sure of was to only ever top it up with de-ionised water from our laboratory at work. This new one in the i30 is the maintenance free type, can't add water.
As for the AGM types, they are excellent as deep cycle batteries and my BMW bike runs one, but I'm not sure of the benefits vs the cost for use as a starting battery. I'm told lead crystal is the latest development as they will not sulphate if flattened.