Hobby Lobby is usually very very good with their recommendations. Unless you have some reason to doubt, I would go with their suggestion. There are probably a 100 good combos.
If you just want to learn more about electric power systems, take a look at the posts noted here.
Sizing Electric Power Systems -
Starts at post 3
http://www.wattflyer.com/forums/showthread.php?t=10304
Starts at post 2
http://www.rcuniverse.com/forum/m_43...tm.htm#4310056