EnerSys NP18-12 or MK ES17-12

I know both of these models are legal (R34), but which is better?
My team is looking to order a pair of batteries from andymark and it looks like they stock both.
http://www.andymark.com/ProductDetails.asp?ProductCode=am-0795
http://www.andymark.com/ProductDetails.asp?ProductCode=am-0844

Either battery is fine. The MK battery is an AGM while the Enersys is a gelcell. The output characteristics, useful life, max output and amp hour ratings are nearly identical. In addition the batteries are roughly the same weight and the size is standard for this battery type. The difference in rated amp hour is merely a difference in the testing, discharge time vs. terminal voltage. If you compare the graphs for each battery they will overlap.

Thanks! We ended up ordering the enersys so our members don’t confuse these with our older batteries.

thats why you should be marking the year of first use on the batteries.

We do, as well as giving them fun names.
But having our newer batteries look completely different from the old makes it instinctively easier to differentiate between them.