First what camera are they for.
Second what will you be shooting.
I would reckomend Sandisk extreme 111.
I use two 8 gig cards with my D300, the write speed is lightening.
I have other 8 gig cards but the write speed does not compare.
OK A bit pricier but you got to pay for good quality.
alison i use them cards and got them off amazon but from another supplier and they was £5.50 (about 3 month ago) complere AV and they was fine too deal with. As for write speed i have never realy found an issue with them.
http://www.amazon.co.uk/SanDisk-Sec...m=A3P5ROKL5A1OLE&pf_rd_r=1JWFCJYA20R5HGJ2MR3W