I don't have either but I do have some Nevada Jack Skulls and some Super Poker World (thanks again EightyWon, RJDev, & Pinesol!) on Chipco blanks. I could see myself with either set (Tiki or EPT) but if I had to choose between the two, I think it would come down to the color of a 25¢ chip and the overall feel of the chips (I prefer less slippery).
I appreciate that the designers of the Tikis took full advantage of what ceramics offer which is full customization instead of trying to emulate the look of typical clay chips. I wish more people designing ceramics would take advantage of this. The EPT chips are a nice fusion of full customization with clay chip elements. Neither are for me but I would choose EPT over Tikis as the Tikis are too cartoony for my tastes.