Many years ago I bought a 100 pack of AmericanLine blades at a hobby show. When I ran out, I couldn't find a source so i went back to Xacto- big disappointment. Then Xacto came out with a blue steel blade, touted to be better than their standard #11. Bought them - more disappointment!
I hope the new Xacto works. The really good news for me, is I found a convenient source of the AmericanLine. The OSH hardware chain carries both the #11 and the razor blades. Here's the link: http://www.osh.com/eng/product/ameri...blades/6637151
The test I use for sharpness, is to make a cut across the grain on a very soft piece of balsa wood. A dull blade mashes the wood, sharp blade leaves a very clean cut. I don't have a good test for durability.
Let us know what you think of the new Xacto!