Anyone had any experience of using a PCMCIA 3G / GPRS data card in a laptop? I've got one in a Director's new laptop and it's really rubbish - far slower than it was claimed to be. If someone has got one and they think it's really good, I'd be VERY interested to hear - maybe I've done something wrong? I certainly hope so as the performance (or, rather, the big lack of it) is causing me a major headache.

Alternatively, does anyone have any better solutions for getting mobile Internet access from a laptop in a car (i.e. no WiFi hotspot, no BT phone line, etc) in the UK?