I recently started using Orange’s new roaming service that allows you to roam on T-Mobile’s network, in the same way as you might roam around networks when you are abroad. So far experiences are very positive. The phone remains on Orange most of the time, which is fortunate as 3G/HSxPA signals are only available via the Orange network. However, when a signal isn’t available, it seems to roam fairly quickly and efficiently onto T-Mobile’s network. The phone sees this as a roam: the same “R” symbol appears on my Desire’s screen. Charges are allegedly exactly the same as via Orange, so in theory it shouldn’t cost anything extra (although I’ve yet to see a bill since I’ve had it turned on).
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