Gibson guitars have had QC issues in consistancy every year. They are hand made to a large extent, and this is where the inconsistancy comes from in part. The woods used also affect this, as in any guitar made by any company. No two pieces ever sound the same. The biggest flucuation to me has always been in how the necks are shaped from one guitar to the next in the same model, year, etc.
Henry is not the greatest boss to work for and this will affect the attitude of the workers there in both a positive and negative way from day to day.
In Japan, the workers have more pride in their individual work and it shows in the consistancy of their products.
I have played several Edwards from different years and they all were equally beautifully done and felt similar. I owned a couple and found them to be very consistant in tone and playability after I set them up to my tastes. The biggest differences were in the sound of the guitars due to the wood being different from one piece to the next, which is normal, but the necks were very similar.
Tokai guitars were very consistant from one to the next as well.
When I bought Gibsons, I had to search through a lot of them over time to find one that I was satisfied with. Every one I ever played was different from one to the next to a greater degree then the Edwards were from one to the next. It could be the way they are tooled, hand-finished, any number of reasons. I think the people at Edwards are more consistant in their hand finishing abilities and strive for more consistancy then Gibson does, but this is just my opinion based on my experiences.