I have not checked your link, but when choosing a mobile broadband stick for myself I ended up with Vodaphone. I had really wanted a monthy contract rather than a year long one, but when I read the site carefully I realised the pay monthly modem was a different design and stated to be a slower speed then the full contract modem. Then they brought in a faster full contract modem about 2 days before I bought – so presumably the monthly contract one may be either 1 or 2 generations behind for speed.
My year contract one logs on ok in the locations I have tried so far, unless I am in a chain cafe (almost any brand) – my netbook tries to log on, goes through the whole system and then I get a message that my stick is faulty. If I leave the cafes it logs on fine. I have no idea if this is a vodafone issue, a general issue with sticks or if the internet cafe has some kind of blocking system to force you to pay for access to thier own broadband supplier.
A friend has a montly vodaphone broadband stick and seems to be getting on well with it in Cardiff.