I have a really limited knife experience, but of all mine so far, the most uncomfortable for carry:
MOD CQD MkII.
I carry in the left-rear, and man... that pointy carbide tip... when you sit down, it sometimes digs in. Also, it's so wide that sometimes when I shift around, it'll push on parts of my rear I didn't know I had.
Not to mention, it has a voracious appetite for jeans. Sheesh. Almost worse than the Buck Strider pattern G10.
I can't carry it anymore... I wish I liked this baby more, since it has a bunch of cool features, an amazing lock, and fits my hand perfectly, but it's just not practical for me as an EDC.
This is in contrast to the most comfortable, an Emerson Mini CQC7. Barely ever knew it was there. A shame, since I couldn't stand the chisel grind on it.
Yeah, I'm kind of on the small side.
-Jon