I finally got my Sanrenmu 605 this weekend. This isn't a review because I haven't really used it, but just some first impressions:
1. Typical SRM quality (lock up, finish)
2. It was very stiff to open at first, but after a little work it's fine
3. Brilliant design
I'll explain my last point a little more. The 605 is a tiny knife. Amazing, it actually offers as much grip as the Sanrenmu 707 (CRKT Drifter). When you hold the 605 normally, with your index finger in the main cut out, you don't have much to hold onto. Also, the knife feels unbalanced. But the whole knife changes when you move your index finger up to the choil. The balance improves, you have enough to grip, and your control becomes outstanding. In the first picture, you can see your total handle distance (from the end of the knife to the edge) is nearly identical to the 707. Is there a trade off of SRM choice to add a large unsharpened area to the blade? Yes, you have less edge. In a knife this small though, I feel the trade off is well worth it.