the kayfun is readily more available and easier to set up.
the Taifun is always on preorder (takes weeks to get it most times), costs more and while not hard toi set up def takes a little more finesse to get it running perfect.
using the same kind of wick in both i see almost no difference between the two.
where the taifun shined is when i used a mesh wick, but it wasnt like suddenly the Kayfun was terrible it was just a little better.
but overall I would take the kayfun for the advantage of simple, almost foolproof setup.
if your interested in these two also check into the SQuape, probably the easiest atty i have ever seen to setup because the coil doesnt short on anything, really nice vape as well, but a big unit and not cheap lol.
as for the machining and quality of the device? top notch on both the TF and KF, german manufacturing at it's finest.