Opera is so much better in this regard: It checks your IP address’ location once during installation and sticks to it. You could manually update your Local State file from %appdata% should you wish to have another country set as default after installation.
For other browsers, I have also been using the NCR or No Country Redirection method to get Google to serve search results in English rather than the language based on my current location.
The main problem with this approach is that https://www.google.co.uk/ncr does not work, so you will have to cope with American search results from google.com instead of which many are useless unless of course you are actually from the United States.
I guess you should use https://www.google.com/ncr