Thank you for taking the time to answer my questions so fully. Yes, I should have said that I'm in the UK.
Just one more thing I need to make certain of before I go and buy my new phone. It's still about calendars - I am self-employed and use my phone to schedule clients then sync to my iMac where I do my accounts using the data in iCal. For this reason I need some reliable method to sync multiple calendars from my phone to the iMac. I've no problem exporting ics files to start with, but how do I keep calendars and contacts synchronised after this? I've read about applications such as SyncMate and the Missing Sync but they all seem to have problems and I can't afford to either lose data or have it incorrectly synced. Have you any experience with these or suggestions about reliable apps to use?
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Thank you to everybody who has replied to my post. I am nearly ready to buy a red S3 from Digigood. I'm in the UK and don't need to go through a network supplier as I have a good SIM only contract - 1200mins, 2500 texts, 1500 mins to landlines and 1GB data for £9. Reading the underwhelming response to iOS6 is helping me make the move - yet again Apple has released something that is very dysfunctional in the UK - last year Siri, this year Maps.