When I first bought Smoke, my trainer said that she thought the saddle fit him, so I just kind of took her word for it. However, he's always pinned his ears when I saddle him - I don't know if this is because it doesn't fit, or if he's anticipating the girth being tightened. He had begun bucking during canter strike-offs, and I originally thought he might be objecting to the way the saddle fit & that it might be too narrow & causing pressure points, however we then diagnosed that he was sore in his left hock, & after a week of the loading dose of his new joint supplements, he didn't offer to buck at all during our first ride since he's been on them & felt altogether happier moving. So I'm hoping it was just the leg causing the issue & not the saddle.
He does not pin his ears or show any signs of discomfort when I press down hard on various parts of his back. Unfortunately, I use saddle pads that are all black & moisture-absorbing on the bottom, so they're not much help in determining fit by looking at sweat stains, & the only all-white pad I own is already badly stained underneath from my old gelding.
I know these aren't the best pictures (it was SO bright outside, & I was using my phone & just had to kind of guess at what I was taking the picture of, + majorly played with the brightness in photoshop afterwards), but hopefully they're good enough for someone to give me an idea of fit? If they're not sufficient, I can try for better pics on Thursday when I'm out at the barn again.
These are the pads I generally ride him with, if it makes a difference:
Kensington Saddle Pads - All Purpose Saddle Pads from SmartPak Equine
ThinLine Contour Pad - Half Pads from SmartPak Equine
(my one objection to the thinline is that it makes it harder to pull the pads up off his withers)