Update,
I went ahead and bought one of these, I got it from toolstoday for $31.00
http://www.amanatool.com/products/ro...nch-shank.html.
Today we started making a custom single speed transmission for our first WCD chassis that we are working on during the off season. We cut our bearing holes 0.01" undersize with our CNC router.
Then we used this router bit, in our old manual mill for the final reaming of the bearing holes at approximately 800 RPMs. Plate was 0.25" thick 6061 T6 aluminum.
It worked perfectly, I'm pretty sure it will stand up to long term use, time will tell. But for $31, it is a cheap and reliable way to finish your bearing holes for a press fit.