What is the recommended way to use the battery? Should it be fully charged every night or is it preferred to run them down to 20% or so before charging? I'm thinking that if I am only using say 25% of the battery's charge on a normal day, that would only require 6 or 7 hours per night to charge it with 110, am I correct about that? I guess I could start off going the 110 route and then spring for the 220 if I'm not happy. Is the battery life compromised in any way by using the 110 instead of 220?