You have considerable price jumps! I am waiting to receive my Mini-Grip in the mail. The more expensive knives are going to have better materials, closer tolerences, and better QC. I don't think you can go wrong with any BM knife. It is all up to which knives you like the look of better, what materials you would rather have, how much you are willing to spend, ect. I would probably choose the 710, because it is supposed to be a very tough knife and it has had very good reviews here on BF, it is also cheap enough that if it gets lost, stolen, or broken it isn't a weeks pay, I also like the way it looks. The Rukus is HUGE, you might want to see one in person or get the new Mini-Rukus. As for blade shapes, I find the tantos to be my least favorite edc shape, it is just impractical for the things I use a knife for, it is very good for self defence and if you need a very strong tip, you may also like the look of a tanto, but I don't. Recuved blades are very good if you have the proper sharpening inplement (e.g. Spyderco Triangle Sharpmaker), they are almost impossible to sharpen on a flat bench stone or on a kit such as a Lansky or DMT, the 710 has a slight recurve. I like the modified sheepsfoot of a Benchmade 555 the best, but that is my preference. Try different blade shapes (you will probably own one or more of each kind), go for the one you like the looks of, or you won't be happy with the knife no matter how well it cuts (unless it is strictly a work knife), if you don't like it, you could always give it to me. Keep us (BF) posted on which you choose.