haven't noticed any performance difference between 6 and 5.5 w/ sp2 and high-encryption pack
however, i did notice that my borderfree link doesn't work w/ IE6
and so, i reverted back to 5.5
the only good thing about IE6 was a few aesthetic changes, if ya ask me...apparently it has problems w/ some links, so who knows what else it has problems with...i wouldn't recommend it.