1.) I have heard good and bad things about American Saddlery. I know they are out of Chattanooga, TN, so I have had the chance to try out many of their saddles(mostly the pleasure and barrel ones though). Basically, quality is ok. It really depends, because they are factory made, and it seems that they get a lot of duds, but I know my first barrel saddle was from there, and it was exceptional. I honestly don't think their saddles are worth $500+, but that is what you pay. lol.
2.) As far as Big Horns go, I would stick with buying an older one. We have one laying around the barn that has been used every week for 20 years now, and it is still in a very useable condition.
Red Money Maker (Red) - 2004 Sorrel QH Gelding