I hate to sound mean, but Opera feels somewhere between the Moller Skycar and a Dyson Hairdryer.
To be fair:
Chrome is fast and adopts tech fairly quickly but kills your battery and your privacy.
Firefox is private and supports new things, but wastes your time.
Safari is battery-efficient, but waste your time and tech lags.
(IE is shit.)
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Conclusion: Pick your poison for the appropriate task and time.