You can download the preview of Opera 15

Opera 15 Next gives you an insight into the next version of your browser.

It should be emphasized that the new release is already based on Chromium, which already guarantees compatibility and compliance with standards. We may want to give it a try even if the older Opera browsers didn’t like us, as there was a drastic change of attitude within the development company.

http://my.opera.com/desktopteam/blog/opera-next-15-0-released