Engine ball bearing turbo vs. non ball bearing turbo?

ball bearing turbo vs. non ball bearing turbo?

what is the difference?

the difference is about 500 rpm of spool... The Ball bearing turbo are the newer generation turbo usually made by Garrett( HKS ), KKK ( Blitz ), and IHI ( Apexi ) and the Non ball bearing are usually Turbonetics ( their single ball bearing turbos suck) and Greddys ( their turbos are usually not ball bearing)...

heres a good read on the subject :
http://www.atpturbo.com/root/technicinfo/bbjb.htm

and of course the newest line in the market GT series:
http://www.atpturbo.com/root/technicinfo/gtvst.htm

thanks