Thanks Justice. The tank can be refilled right? The atomizer in the ego t is not compatible with regular ego is it?
The tank can be refilled and the t-atty is compatible with all ego batteries.
As far as your OP:
Advantages of auto battery
Only 1 - some people find them more satisfying. I personally switch between kr808 auto and ego-t when vaping. Typically of me, I do it backwards from how most would - I use kr808 when I'm at home and ego-t when I'm out and about. If someone made a kr808 auto battery with the capacity of an ego battery or better, plus a carto to match it, I'd toss my ego batteries in the trash. I find the auto battery that much more satisfying.
Disadvantages of Auto battery
Can't drip since this is very likely to kill the battery.
The "It might activate in your pocket" warning is pretty much limited to the old switches when auto batteries first came out. The auto batteries (at least the kr808 ones) currently being sold by decent vendors are no more likely to go off in your pocket or purse than an ego battery. I'd actually say they're less likely to do, since it's easier to accidentally hit a button than create the right noise/vacuum to cause an auto battery to fire.
The only other disadvantage of the auto batteries is since they only come in mini sizes, they feel a little more fragile. I'd be afraid to stick one in my pocket unprotected by a case. Of course, I don't stick the ego-t in my pocket either. I stick it in a lanyard around my neck.