Maybe 4-5K. That is probably pushing it though.
I realize that I am in a small group here, but I really get off on a gun being, feeling, and sounding smooth. There is a guy who shoots with us who built his own gun by hand, with no power tools other than a dremel. (so he says - doesn't really matter for this example) He hand filed and lapped the slide to frame. The gun is rather ho-hum looking, but I love running him just so I can hear when he racks the slide. It just sounds so silky.
My gun shoots great, I just hate the way it feels/sounds. Maybe a trip to a smith is in order. Should they refit the slide altogether, or just lap the rails?