I have just contacted 3 in the uk and the lovely Indian lady in Mombassa confirmed that 3 sims wont work in Nokias unless they are supplied by 3. She suggested I pop along to the 3 shop to get a free upgrade to an N97 or some other make....
I politely declined and asked when I can cancel the contract instead as I dont see why I should be restricted to using the phones only they supply.....
They might have better usage deals but actually the overall service is poor and customer service is even worse. Since getting a vodafone sim I have great reception and every time I've rang them I've even spoken to someone sitting in the UK as well
My Vodafone SIM only costs £20 per month on 30 day contract with 600 mins talk, unlimited text but only 500mb usage. I will see what the additional cost is next month if I go overt that limit.....