I have 2 VTC Minis, and have also had the original VT in the past. The original VT wins for battery life, but it does take longer to charge. The mini is nice since you can swap in fresh batteries. Also the size is extremely compact and pocket friendly. I use Uwell Crown
tanks on both my VTCs and run Nickel
coils in temp mode.
The only issue I have seen is that after about a month of use on both units, I have to use a higher temperature than when my units were new. I used to vape at 420-480degF on the Uwell Crown/Ni200 coil. Now a month later I am setting temps 480-570degF. Have tried 3 different
tanks with fresh coils, etc...
So beyond the strange temp variation over time I have not had any other issues. Also I will add that the original Evic VT seemed to give me better more consistent hits over the battery life, talked to a friend that is an electrical engineer and he said the Lipo in the original is much more powerful than a single 18650 battery, which makes sense..as the original VT has a ~5000mah 11.1v 3 cell Lipo.
Since there is no firmware update out yet, I would recommend the original VT unless you need the very small size.
Good Luck!