I recieved a Boge V2.1 last week
I have only used my old 510 cartos and atty's on it(pre-filled) and have yet to fill/use the tank, I havn't needed to use the Boge carto's yet as the 510's are working fine.
I have also tried my clearomizer on it.
No issues so far as to performance or flavour, only when the clearomizer wick needs to catch up or the Atty/cart is running low does the flavour start to go bad, In that case I just top off or tip the tank.
Cartomizers have some special needs when it comes to filling I find, you can throw 10 drops into a new cart, blow out the excess, install, and get a dry, burnt vape.
It can take some time for the juice to soak into the core, that time depends on the thickness of the juice, temp, phase of moon, yadayada...
Even a top off can take a bit of time to soak deep, attys with cartridges are faster but have less capacity and don't work all that well with the tank fill feature.