Was looking for memory cards for a new Nikon D90 SLR. This is a fast camera & if you want to get the most of continuous shooting you need a fast card.
This sandisk is the fastest on the market, and sandisk worked closely with Nikon to optimize it's performance in their cameras. All the SLR forums I've read support the fact this is about the best card out there.
If you don't need continuous shooting get something like an extreme II 15 Mbps (ie from 7dayshop) instead. I decided I'd get one super-fast card, and top up capacity with much slower cards.
This is the best price I've seen. Most other places it's around 50 UKP+.
Note this is the NEW FAST version of this card. The older card is only 20 MBPS yet is still listed as "extreme III". You need to check the card/box clearly states 30 MBPS edition in big letters on the front
a) On the web site/photo it shows this as the 30 MBPS edition
b) At the argos tillpoint in-store it states the description is wrong, and this is the 20 MPBS card
c) As I'd driven to collect a reservation I asked to inspect anyway - and it was the 30 MBPS card.
So I have no idea on what % of cards are 30 vs 20 in argos -- I'd guess new stock is faster, so YMMV on this deal.