I just got some ego-t tank tanks from eastmall and the caps are different than ones I have before. I think it is a new cap design. So far its working fine. I'm hoping these have been redesigned to address the leaking problem. We'll see. Instead of a hard plastic cap it seems to be more of a soft silicone plug. Also they did not come with a cover like the old ones did.
Here is old and new side by side. New is on right.
Here is old and new side by side. New is on right.

