NorthStar 100FT Red battery ??

[deltaten]

I have source for the above batteries, having been used as back-ups at a power station. They are dated 2014 and supposedly are changed out each year (?) NSB specs say 1200 duty cycles at 60% DOD @ 77 degrees and 15 yr life at float. BUT only 2 year "shelf life"! The " blue" batts are specd'd close to the same; 2000 cycle, 50% dod; but apparently have a different chemistry,as they are spec'd for mobile lift/tractor/lift use

Sample I had hands on still showed between 12.9 a d 13.1 volts. This is after having sat around a warehouse for, what, two years?

Considering plopping 4 into the boat, for the cost of a little better than the cost of another single Interstate 160 ah deep cycle group 27. I'd have to buy 3 of those @ roughly $400 to equal the a/h; but only 1/3 to 1/2 the duty cycles!

What say the experts/experienced? Think it's worth the $150 chance? Pay the $250 difference for a 5 yr pro-rated warranty? Wasting time and $$ ?

TIA,
Paul