Have been using the beta from some time now. It's pretty good. I had moved from firefox to opera but am moving back now. I especially love the new auto-complete bar. It is a brilliant feature. It auto-completes based on the website page title as well as the URL and also remembers your past visited sites ordered by visits.
For example, I visit 'google.com/translate_t' a lot. In Opera, it comes below all the other google pages 'google.com/search**'. In firefox, now I only type 'tran' and it auto completes. :hap2: