Down here, in Australia, LiFePO4 batteries are all the rage, I suppose because of the widespread camping and motoring community as well as our very high reliance on solar power.
Their only disadvantage, compared to a marine grade lead-acid battery, is cost, but I feel that that is recouped over the years of usage (10 years +).
It is very much the technology which will be replacing lead-acid batteries once the costs drop and is extensively used in electric cars, electric wheelchairs, etc.