People PLEASE stop referring to the genuine vs. knockoff/clone arguement when clearly there's a design flaw (same flooding issues reported from both type of sources). T3 relies on gravity and the negative pressure buildup in the main chamber created by suction to draw the eliquid to the wick/coil. If there's too much gap in the wick slit, it'll draw the eliquid faster which leads to massive flooding, but too much wick will pinch the wick leading to dry hit/muted flavor. If this wasn't enough, the viscosity of the eliquid is also a factor in determine the flow; i.e. high PG% flows better and tends to cause flooding when compared to high VG% eliquids. Some manufacturers tries to band-aid the issue by increasing the air hole from 2 to 3 to reduce the inner chamber pressure, the result is hit and miss in solving the flooding issue but this leads to an airier draw. While some have luck with the stock wick/coil when vaping with their preferred eliquids, the results may differ significantly based on the inconsistency of the wicking material, number of air holes, the strength of draw from the mouth piece, and the type of eliquid you're using.
How to remedy the flooding issue? (1)place additional "flavor wick" to plug the wick slit and reduce the flow of eliquid or (2)if the head only have 2 air holes, try drilling an additional air hole (3)rebuild the head altogether (use more wicking material). However, finding the right amount of wick material to prevent flooding/dry hit does takes some trial and error.
Some member mention that the leakage may due to the silicon grommet not creating a seal. The best way to test this is to inject a small volume of eliquid enough for wicking but doesn't reach the seal and see if it floods. If it doesn't flood then it's the grommet, if it does then it's either the silicon grommet or a combination of all the different factors mentioned above.
The bottom line, like most finicky POS made from China, don't get it if you're not willing to take time to understand how it works and learn to troubleshoot it. If you don't want to deal with the hassle and inconsistency of these then you're probably better off with a carto+tank setup and hope no more occurrence of similar incidents of Bogegate in the near future...