I just talked to Mike, first he wants me to send the jacket back to him for the inspection. He also mentioned Vanson is now using different competition weight leather from before.......
From what I have been told by multiple dealers Vanson no longer gets their leather from the tannery that made the comp weight leather that we all love. Vanson has struggled in recent years to get a comp weight that is similar to the comp weight of old. Some leather has come in too heavy and stiff, other too thin and supple. I know they had a batch last summer that was so thick they used it for bags because it was too heavy for jackets. The last jacket I ordered from Vanson was delayed for over 40 weeks due to shortage in comp weight leather. In the end when the jacket arrived it did indeed feel thinner than any comp weight from Vanson I had felt before... and I've owned 8 Vansons. I only have one Vanson left. It is a Model B purchased about 2 years ago and it is more supple than other comp weights that I have owned before, and maybe a touch thinner (looks similar to your Enfield). While I love heavy stiff creaky comp weight, I have to say I have greatly enjoyed this more supple comp weight. It is so much more comfortable to wear and it broke in pretty quick. It's still thicker than just about any other jacket I've owned outside of my old Vanson "e" that was mistakenly sold and my Lost Worlds J23 which is 3.5oz HH.
All of that to say, yes the comp weight is different because it's being made by a different tannery than the comp weight of old. But that doesn't mean it's worse. There does seem to be a lot of variation, so it really depends on the batch. Personally, I think your Enfield looks really nice and I would wear the heck out of it and not look back. If it was a 42 I'd really consider buying it off you if you were unhappy.