Alex,
I've been using that exact battery pack for the past 3 months. I probably don't tax it very hard, as I'm using it to start a .46 2 cycle. Your mileage may vary on how often you need to charge it. I get out to the field usually once or twice per week. On that schedule, I've only had my starter on a charger once so far and it is still going strong.

Cheers!