That's cool, we all complained to GV about including the caps with the mod. Costs them pennies to make and shouldn't have been an accessory.My wifes' Aegis came with caps and adaptors for every battery type. Along with the excellant Shiels tank. For fiddy bucks.
I have 5 start 20700's and a 21700. I use them in the Pulse and Capo and sometimes she uses them in the Aegis. The 20700's are pretty unimpressive. The 21700 has very good battery life.
For the ampp rating I'll be staying with 20x's but for battery life forget it. 26650's are better for life by far under 50w. Of coarse over 50w is where the 20700 shine.
Good to know about the runtime, I use the iJoy EXO RTA on the Aegis at 55W and it's a good tank for it with a simple clapton.