Bonsour Jay,
I much prefer direct fit myself. They are smaller, easier to handle. If I have to take them out of the case, for some reason. (the ring can be a pain; sometimes in this instance). And I am not sure of the long term effect on the strike. Most of the display cases, for $10 strike cases are sized for the direct fit size. Except, for special cases(red, blue, pink, etc). I am switching all of the newer big case $10 strikes to direct fit airtights.
And, another BIG factor the direct fit is cheaper. Which can make a difference. Over the number of cases that could be used, in the switching process.
Happy switching,
Dan