Tevin,
each of the ones you linked to are ones that I thought about getting
the cell balancing should be standard shunt limiters and should work just fine
looks to me like the 12V, 12Ah one has a charger included and the smaller one does not.
you really should have a matched charger as far as current and max charge voltage so the shunt regulators in the cells don't overheat ,
so I would tend not to get the one without the charger (even if I only tested it to reproduce something close with solar charging)
this is also one I was looking at
http://www.amazon.com/Bioenno-Power-applications-wheelchairs-photography/dp/B00PGTOHJK/and was available 2 weeks ago on amazon, but is not now unavailable there
but might be better to get it direct from who makes it
http://www.bioennopower.com/collections/lifepo4-batteries-for-communication-equipment-ham-radio/products/12v-12ah-lfp-battery-pvc-packcontinuous discharge current is 24A, with a peak of 48A, so pretty good there
already has the power pole connectors on it !
not sure how to add it to cart with the charger though, but they have the phone number at the top of the page to ask them
if all fairness, I am not sure it will matter that much what one you get as they are all going to work
by the way, do be careful of lead acid equivalent ratings,
for example, the SHORI battery that is labeled at 14AH is actually a 4AH battery
and yes I own one and would rather not.
if you only need 2.5AH and 5A max (like if you are running the ft-817), get 4 protected 18650 cells, should be about $20
get 8 cells if you want 5AH and it will only be about $40,
cell holders will be a bit more if you want it to be easy to hook up, but still way less than other options