Perhaps this will help.
I used to have a Gerber Gator with a thumb stud
opening, and it seemed like a great thing.
Nothing wrong with the fact that it was
a Gerber, or a thumb stud -- but I carry
in one of my front two jeans pockets, and
it seemed like the thumb stud always got
hung up when I reached in to retrieve the
knife - thus, it would start to open at
worst, or take some monkeying around to
remove it from my pocket at least.
Perhaps that was a sign that I need to buy
jeans that are less tight, or that I need
to lose weight

, but in either case, it
was annoying to have a folder take longer
to remove from my pocket because the thumb
stud was hanging on to the edge of my pocket.
So, I much prefer holes for opening. Don't
own anything else now.
If you were to carry in a sheath, this would
not be an issue.