I tried this:
Computer A 4 years old Dell with Windows XP SP2, Intel 2200 wireless card
Computer B new Dell with Vista and without SP1, Broadcom wireless card.
Computer C new HP with Vista with and without SP1, Broadcom wireless card.
Computer D new Dell with Vista with and without SP1, Intel 3945ABG
I copied 22000 files (18000 relatively small) and folders with 145Mb from the server to the computer one at a time.
I used a wireless AP Netgear WG102 connected to a LAN and a Windows 2003 server where I had the files.
The AP was 25 meters away with 3 walls between the AP and the computers.
Results:
A : 5 minutes
B and C without SP1: 25 minutes!
B and C with SP1: 19 minutes!
D without SP1: 18 minutes
D with SP1: 13 minutes
When I connected the 4 years old Dell with XP2 to 100Mbit LAN the time was: 2min 50s
As you can see: SP1 makes the computers copy files faster but it is a long way to XP with SP2 - I have not tested SP3 yet.
How can I make the Vista computers to go faster? It´s a long way to the speed of XP!