I researched all kinds of straps last year, when I knew I wanted a ukulele strap. Although the hook system has been around awhile, and many people like it, I didn't like the concept of the sound hole hook for 5 reasons:
1. It puts pressure on the thinnest part of your ukulele (possibly causing a crack), and could, with repeated uses mar the finish at the sound hole.
2. It restricts the movement of your sound board. Maybe not a problem if you're plugged into an amp.
3. Looks ugly. Why take a beautiful uke and add an ugly hook and strap to it's face?
4. Not secure... if you accidently let go or drop the uke... it may barrel roll off the hook and fall to the floor. If it does hold on, it just gave your nice delicate soundboard a nasty tug.
5. I don't like having weight slung around my neck.