Did you use rechargeable batteries? If so, then try duracell batteries, as they recycle quicker. I used a set when photographing the Christmas parade on Saturday in Birmingham on half power, and was able to get two shots in quick succession with only a small delay before they recharged, and they were batteries I had in there for some months. As to a Quantum batteries they will cost about £300 and the lead another £50 or so. Can't use it with my Nikon SB600 as it hasn't got a connecter to plug the battery in.