Your wall adapter will work, but a higher rated one will charge faster.
LiPos don't have any issues with being recharged before flat (i.e. red), and may last longer if recharged before flat. Their "life" is given in recharge cycles, typically around 300, but that's based on full discharge. Less than full discharge is said to give longer life.
I've only had my MVP for about 6 months, so I can't give any empirical results - other than that I usually recharge at yellow (or before - when the counter gets towards 900 I recharge it, mostly so I know I'm good to go!)
I also use a wall adapter for charging all my
devices. I figure in the worst case scenario of a battery or charger having a catastrophic failure (i.e. going up in smoke!) a wall adapter is cheaper to replace than my computer's mother board.