Not knowing the OP in any way shape or form... I think that the answers being provided are obviously unhelpful. They in no way, shape or form are addressing his question. Using basic logic and reasoning skills then looking at the equipment he is using now and the question he asked, it becomes obvious that he is not interested in a single cell device from Eleaf or Sigelei. An individual who is using a 100W dual battery device at 15W and a 7ml capacity tank is obviously interested in the convenience of not filling/charging frequently or were oversold the device to begin with. As he is asking about another high wattage dual cell device it is obviously the former as opposed to the latter.
Although there is a quality difference between the devices, you will not see any functional differences the way you currently vape. The Eleaf has in device charging and with the parallel battery configuration will last slightly longer on a charge then the Sigelei. They are both obsolete units so upgrading from one to the other makes little sense to me unless you find a killer deal on the Sigelei and already have a stand alone charger.
