Pics of my 1540s. Both have the (very high-quality) leatherette headband available from that Amazon seller. I use it to protect the apparently non-replaceable OEM pad. Be aware that it does take up some vertical space, and the Shure is a bit vertically challenged as it is. If you have a short head like me it will be fine, but if you're Peyton Manning then fuggedaboutit (go pick up some Yamaha Pro 500s instead, I loved their SQ but even at minimum extension they just flopped forward on my head.)
The 1540 on the right has the Alpha pads. First off, the pads are of superb quality, but I can't recommend them for the 1540. The problem is the angle is just too steep. Whether or not I have them angling forward or backward, the fit is not good, because the cups are almost dead-on in the horizontal direction, and so is the side of my head. I tried the suggestion made above about rotating them so they angle upward or downward, but then my ears don't fit because the cutout is rectangular, not square or circular... and I have medium-big ears (for example, the V-Moda M100 stock pads are very uncomfortable on me.) Oh well. I did not really notice a big sonic or isolation difference anyways, pressing the cups against my head to simulate a good fit. However I do love the genuine leather material, although the 1540 OEM pads are still excellent.
I am curious if the unangled Leather Dog pads fit better. Luckily MrSpeakers forgot to send me the third pair of Alphas I ordered, so I emailed him asking to send me a pair of Leather Dogs instead. I'll be keeping the two Alpha pairs in case they fit better with other cans I may own in the future.
I was trying to find the post with the Amazon seller of the wrap above, think that might help me as well, have a small head, often hard to get fit that doesn't flop. Couldn;t find it-could anyone post the link again? Thanks