You won't gain any download speed as this is determined by many factors the biggest one being the service you subscribe to from your ISP, i.e. 512mb, 1mb, etc. If however and I'll presume you have 802.11b wireless adaptors as you don't say, you want faster file transfers between pc's, by all means upgrade them, you will see an increase depending on which ones you go for. If your reasoning is to achieve faster download speeds from the net using new adaptors then you won't see any increase. 802.11b has a rate of 11mbps, no uk isp currently offers anything close to this speed so there's life in them yet.