Battery confusion please help.

[sparkyslots]

Ok before I start sorry sure this may have come up before but can't find my answer.
So here we go, I have an X6 VV and a K100 for this.
The X6 is rated for 1300mha which is 1.3ah's yet this thing will last me a good 11hrs before it needs recharging. Using a Protank 2 with a 1.8 coil. not bad.
Now my K100 has a 2900mha battery a 18650PF to be exact. This battery being 2900mha is equal to about 2.9ah's. So our rule is this fully charged at 4.2 when the voltage drops to about 3.6 to 3.5 change the battery. So using the same protank and the 1.8 coil am I getting less time than my X6. My K100 is good for about only 5 hours before my battery needs to be changed. I would think it would last longer than the X6.
Now here is one more same tank same coil. On MVP at 7.5w's I can run for about a full day before I need to recharge the MVP.
Curious and sorry if this is a repeated thread.
Thanks

 

[chimsweep]

Your ratings are correct, but every battery has it's own personality. Though each one lives up to their rating mostly. Is one battery older than the other? I have read MVP's run up to 2 days before charging. My son uses one and that's his mileage. Need more info to be able to give some definitive advice.

 

[sparkyslots]

No the batteries are only about 3wks old. (18650PF). As for the MVP its my fault I tend to chain vape a lot. Yet my K100 seems to be my most favorite. This is why my question above has me stumped.