Seems grand to me. No problems at all. The multi-tasking is great, as can watch a noddy video whilst answering email.
My Irish work colleague moved from iPhone to Samsung two weeks ago and they described the phone as one of the
"most hated pieces of shite they have ever been sold"
They since have returned the phone to the Vodafone shop and have asked for an iPhone 6!
Sorry to take so long replying, just home from Wolves. It's a modest iPhone 4S
The other curious thing is that prior to the upgrade I was out of memory, and when I checked the Mail memory was 1.1 GB. Now I have 2GB of memory free and Mail has gone down to 78MB.
Not to mention that it keeps freezing or closing apps whenever it fancies. Cracking stuff.