Vodafone has a pretty good price on the Sony Ericsson W910 handset now. It looks like my current phone minus all the annoying cosmetic issues (matte instead of glossy so it doesn't look gross, different keypad design) plus 3g. However, I've heard tons of stuff online about the software being crappy - the phone crashes and restarts all the time, and the battery needs to be taken out for it even to turn on again. There have also been suggestions this varies from carrier to carrier, firmware version, and manufacturing date of the phone.
Is the W910 sold by Voda in NZ stable? If I go buy one, would I be able to exchange it for a different phone of the same value (eg K770) if the phone turns out to be unstable and crash prone? Does updating the software yourself void your warranty, and if so, would Vodafone do software updates from Sony to try and resolve a problem, or would they not want to as it's not their modified/branded software?