Since we're talking about the jackets, I would recommend checking out this very comprehensive thread on the main FC jacket that Tyler wears:
https://www.filmjackets.com/forum/viewtopic.php?f=16&t=4503
As you can see, there are 2 versions of this jacket, so screen accuracy depends on which version you are looking for. Actually, only one was used in the movie, but the original version is still "accurate" in a very nerdy way.
As for the Soul Revolver version of the Mayhem jacket, I haven't touched one in person so I can't comment with a lot of accuracy, but from what I can tell from the pictures, the JAL version has some minor things that make it more authentic looking to me than the SR version. Of course, Jonathan A. Logan did make the Mayhem jacket, so it's no wonder, but the current SR version is very close at this point. If JAL wasn't making them, I'd go with SR.
There are some old SR Mayhem jackets out there that aren't very screen accurate, because they have revised the design so many times. At this point, they use JAL's version as a reference. Mainly, there are 7 ribs on the arms, 5 on the lower shoulder/top arm and 4 white ribs on the top shoulder. My main issue with the SR version is the ribs are not as "full" and nicely bubbled as they are on the JAL version. There are some good shots online from Fight Club showcasing the luscious ribbing in the JAL version. They are very nice when silhouetted.
There is also ANOTHER version of the Mayhem jacket. Shown here:
https://www.filmjackets.com/forum/viewtopic.php?p=4451#p4451
You can see that this version is busier on the front and has an asymmetrical zipper design. It is my belief that this version is based off a vintage Moto Cuir jacket. Seen here:
**Fight Club Jacket** just came in... - Vintage Jackets and Helmets etc. - DO THE TON
Clearly, it seems to be the inspiration for the Mayhem jacket in it's current state. Would be cool to find an old vintage Moto Cuir in red.
Anyway, that's my nerdy contribution on FC jackets.
edit: Just wanted to comment and say that the Moto Cuir jacket may be the same jacket used in the shot of Brad Pitt. Since it's black and white, it may well be a black Moto Cuir. Hard to tell. Just wanted to be clear about that. There is also a gorgeous blue version of the Moto Cuir jacket. Not very Fight Club related, but a great looking jacket nonetheless.