I used an ogilivy half pad on my tb for a couple of months and he ended up with a sore on his back. My saddle fit, as I had it checked by multiple saddle fitters. Once I switched to a thinline sheepskin half pad the sore went away.
I love the looks of ogilvy, but it didn't work for us. I will continue to use their regular saddle pads though :)
I would say if your horse has a sensitive back then oglivy would be great, unless your horse has a round barrel in which an oglivy would be too much padding. I've heard good things about thinline (only had issues with it not being correct padding for saddle fitting purposes). Fleeceworks are very nice and can Easily adjust for different horses and saddles. Never heard anything about beval tho
They are very high quality. I've never known one to fall apart. They have great memory foam and cushioning for the horses back. My one issue is that they are a bit thick, and so can alter the fit of your saddle, but I still love them.