I have a 550 Griptilian with the modified sheepsfoot blade and oval opening hole that I recently purchased. The reason I chose the sheepsfoot blade is that it comes with the hole, and since it is a modified sheepsfoot blade design, it does have a some what useable tip to it. Also, a plastic zip tie attached to the hole, and I can wave it without a problem since it is a tip-up knife.

The zip tie trick waves better in my opinion than an Emerson wave dependent upon the size of the zip tie.
The 550 and 551 are full size knives. The large Grip fits my hand perfectly. You might want to consider the mini Grip because the full size Grips are a pocket-full.
The axis lock is an awesome lock, and it is ambidextrous. For that matter, there is no left or right handed model for the Grip because there are clip screw holes drilled on both sides. I don't really like this feature because it interrupts the flow of the handle, but it does give me the option of carrying it in my left pocket if I so desire, so it's just really a trade-off for me.
The only things I do not like about the knife, besides the carry clip screw holes being drilled on both sides, is that the axis lock is not as smooth as other liner locks that I have owned, and I have owned a few of the axis lock type knives. The Benchmade 800 AFCK and SERE 2000 are a lot smoother than an axis lock, with the SERE being the smoothest factory liner lock that I have ever had the pleasure to open. Also, I wish Benchmade would scallop the handles where the thumb rides up to open the blade via hole or thumb stud.
Other than the above mentioned, the Griptilian is an excellent knife with great ergonomics that is priced reasonably for such high quality and is a best buy in my opinion. Get the Grip!!! Big D1