Actual Performance, Perceived Performance

Hi, all. I am not a programmer, but i have a question relating to vista file copy speed.
If it has problems copying due to its i/o buffer or whatever it is. Surely this will have effect on the read times and thus loading times. So I see it was mentioned that they went back to xp algorithm I can see no real evidence of that. Yes the speed has improved but it is still slow.
I backup my 1tb of data from my two internal driver to a firewire 800 external hdd. Now under Xp this takes about 3.5 hours. Under vista sp1 it takes… over 16 hours. Which personally i dont want to wait for.
Anyway, I shall be stopping with XP until someone mods vista until it works and a reasonable OS. However I do feel it will be another WinMe experience…