Well, yes, bearing life is inversely exponentially something-or-other proportional to speed, but it depends on the meaning of "as long"...
Just Gary, remember this post by Greg Jackson. In it he says
andBy our estimate the spindle design is fine for anything up to 7000 RPM. Taking it higher is certainly possible, but will lead to shorter bearing life.
To me that sounded like 7 krpm was an acceptable running speed. Maybe I'm being wishful, but if the bearing life at that speed is equal to the useful life of the machine otherwise, "as long" is long enough...We agree with one of the posts, 180F to 200F is a fine range for the spindle bearings at top speed.
Randy