I have a SC1 carrier. I keep it in the car as a reload for my EDC L4. It is an incredibally well made carrier. It is tough as nails, water proof, and very small.
You would NOT be dissappointed if you bought one....
BUT.... If you want to carry a LOT of batteries... OR.... if you have a monster like a Surefire M6 or an M4... you might want to get one of these. I have 2 of these... and i think they are THE BEST battery carrier, hands down. They are completely waterproof, & they are incredibally strong.
Pelican 1020 Micro case. I bought it from botach.com... and it came PRE-CUT for the batteries. That was a BIG selling point for me... because I did NOT want to cut the foam myself, and I could not find a pre cut foam case anywhere else.