I love my 551 Griptilian. I just like the more full size folders as opposed to those mini's. I had the round hole version a few months ago when they were new, and I just didn't like it as much. I felt that with the hole I had to follow through when opening the blade. The thumbstuds on my 551 allowed me to sort of flick the blade open.
That thing has survived hell and high waters here. When I first got it, it went everywhere for a couple of months of EDC. EDC for me was Every(where) Daily Carry, which meant it went camping, fishing, to school, work, we went bar-b-q'ing together too. I don't recommend this, but it did baton through hardened mesquite wood really well.
The Griptilians (and mini's) are just that all around utility/survival/do-it-all knife for a really great price.
As for those Ritter Grips, they are a nice looking knife, and Critter (that's his username here), is a great guy who designed an excellent blade for what is now known as the Ritter Grips. The price difference may seem a bit high, but it's all up to you guys to see what you think is worth it. I just got an S30V Dejavoo, and have used my Rukus on several outings and the edges are still shaving sharp even after carving up and making a home-made bow over the weekend. I really like 154cm, it's one of my favorite steels, but S30V was chosen by Critter for a reason. The blade shape also gives more belly for slicing and/or doing bushcraft duties. Plus you get the awsome name of having a "survival" knife

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