Got the ZK SG2 yesterday so I've had time to check a few things. Most of these pics show the ZK SG2 compared with the carbon ZK that I bought a year ago. The carbon ZK weighs 300 grams, the ZK SG2 weights 316 grams. Both are 61 mm at the heel. The carbon ZK has a better distal taper on the tang and towards the tip. The ZK SG2 tip is not very flexible while the carbon ZK tip is. Fit and finish on both are very good. The balance point on both knives is about .5 inches forward of the bolster. The ZK SG2 OOTB edge was quite good. The choil is nicely rounded and polished as is the spine.
All in all, I like the ZK SG2 a lot. Is it worth $450? It is for me.