Thanks for your comment.

As our phone was a review item, we actually don’t know its version of firmware, however the phone was a few weeks old so would not have had the very latest version, if a new one is being released this week.

Checking the Sony Ericsson website, I notice that they will be upgrading Android to version 2.1 later this year, which will be a benefit, though I see a few users are unhappy that a move to Android 2.2 is not planned at this stage:

http://blogs.sonyericsson.com/products/2010/05/05/sony-ericsson-xperia%E2%84%A2-x10-to-get-uxp-upgrade-in-q4-2010/

If you buy the Xperia X10 over the Internet, you will be eligible for the 7 day return under the distance selling rules, though you should check with the provider first just to make sure, given the news yesterday about the confusion over contract cancellation policies.