Cyberclinic: Is it too early to buy into mobile broadband?

How does mobile broadband compare with the fixed-line variety? We're now seeing a massive landgrab by Britain's mobile phone networks. Four of them (T-Mobile, Vodafone, 3 and Orange) are trumpeting their mobile broadband services, trying to sign up subscribers. Each gives you a USB dongle that plugs into your computer and connects you to the internet via a 3G network. But who are they best suited to?

Judging by your feedback on the Cyberclinic blog, speeds over mobile broadband connections differ wildly. An email from Ben Werdmuller salutes his new convenience: "I can go online on my journey to work. While it slows to modem speeds for parts of the journey, when I'm staying still – particularly in London – it's as fast as my home broadband." But Alex Hudson, on our blog, isn't so enamoured: "Overall, I realistically get around 1.5Mb – nothing like the advertised 3.6Mb."

Three of the companies boast 3.6Mb connections, while Vodafone offers an impressive 7.2Mb. Michael Phillips, product director at Broadband Choice, acknowledges that all the dongles perform "reasonably impressively", but he doesn't believe that, at the moment, you'll get the same performance as from a fixed line.

His bigger concern is the limits on data downloads imposed by the contracts, and charges levied should you exceed them. Many deals offer a 3GB monthly limit; until recently, that would do for most people. But with the huge take-up of services such as the BBC iPlayer, data transfers are going through the roof. Still, mobile broadband is very useful for two groups; students, and visitors who might not be stay long.

Of course, as "Broadband Girl" says on our blog, 3G broadband is still in its infancy, and advances should boost speed and reliability. Right now, the companies that might be feeling threatened are providers of Wi-Fi hotspots; an Ericsson executive last week called them the "telephone booth of the broadband era".

Diagnosis required

Email any technology gripes to cyberclinic@independent.co.uk, or join the discussions on the daily Cyberclinic blog at www.independent.co.uk/cyberclinic. Currently under discussion: which pieces of now-obsolete technology do we get most nostalgic about?