With Kai you place the order, you get an acknowledgement email and then absolutely no further information about the status of your goods. Inquiring emails are ignored. Then one day, as you're starting to wonder whether your order was shipped at all, you get it in the mail and say "thank goodness".
DX, in contrast, tells you everything that happens, including shipping (likely to happen more than once if you order more than one object) and delays, and they're pretty quick to answer to tickets.
This is just my experience, so YMMV, but I definitely prefer DX.