This past month I've been running a .500" 7-flute finishing endmill from Fraisa in 440 Stainless. I must say, the results have been exceptional. Due to the high helix of this tool, they recommend only taking .008" per pass. I've been running the book values, which suggest a spindle speed of 1985 RPM's and a feedrate of 17 inches per minute. Right out of the gate I was achieving a surface finish of 16Ra. As of part 100, we are still seeing a surface finish of 16-17Ra, and the tool hardly looks used. Keep in mind, I'm finishing roughly 31 linear inches per part. I have this in an ER32 collet, and haven't experienced any tool pull-out.
This is my first time using a Fraisa tool, but definitely not my last. They offer a wide variety of cutting tools, and you can even buy directly from them, from their website! Check them out by clicking on the link or picture above.