Hey miro44, I'm not too sure about the HT on Kershaw's 440A, but I own a few other Kershaws with that steel. Unless you've found an older Blur (New old stock), the standard model comes with a blade of Sandvik 13C26. You can also find S30V and SG2 blades (My personal favorite, the SG2 is like a folding scalpel!)
The good things are that 440A seems to be very resistant to surface rust (I've not yet had a single spot, and one of my knives was dropped in the fish tank!) but I do take care to wipe the blade down on a regular basis. The edge retention is good, as I can do normal cutting tasks for about 3 to 4 weeks before needing a touch-up. To most, the edge would still be fine, and sharp enough to continue with normal cutting chores, but I like the razor edge. That's another good thing about the 440A. It will take a razor edge, shaving sharp, and is very easy to resharpen or touch up. If you plan on doing a lot of work-type cutting (cardboard, rope, mulch bags, etc.) I'd suggest stepping up to the S30V.
As for the Blurs, they've become my favorite EDC knives. Excellent ergos, tip up carry if you wish, and the SpeedSafe activated thumb stud fires the blade with authority and the lock up is excellent. There are some good pics
here. They mostly refer to the S60V Blur, but there are some very nice pics of the other Blurs, too.
All in all, the Blur is a great value for the $$, and Kershaw's CS and lifetime warranty are excellent. I don't think you'll be disappointed.
Miro, I should have included a link to the
440A to 13C26 Change Over Dates thread...hope this helps.......