The appealing maybe the price at this time for the AGM, however little further down the road you will most likely require to invest a lump of cash to replace the internals. I would take a moment to evaluate the difference if you were to spend your money on something that would function out of the box and stay functioning VS something that is cheaper but may possibly require a complete internal overhaul.
Hit up google and find find all the costs of each individual required replacement part listed by Racing.
For this example I will use WA and AGM, feel free to replace WA with whatever other brand you wish.
If AGM + replacement parts < WA
If AGM + replacement parts > WA
If AGM + replacement parts = WA
"Its only a little bit on fire"