A month or so ago I purchased a box of ECCJs. After a few weeks in the humi at 65% humidity I decided to try one. I too experienced some tunneling due to underfilling. The cigar was smokable though. After looking at the rest of the box they all seem to be a little under filled. The 2nd cigar I smoked burned fine but was a little hot due to the loose fill. It seems that there is a possible trend here with construction issues.
Bob