I changed mine to angular contact bearings. I used 7007B and 7005B bearings. You need to make spacers to use them since the tapered rollers are thicker, but it is not difficult to do.
The ones I used were from VXB and were part numbers KIT8891 and KIT8889. I have run them up to 10,000 RPM without trouble, though I can't speak to their longevity yet.