Namely, speed boost and Mail have continued to be refined and are now at the point where Opera is satisfied with them.  In testing by BetaNews, the Turbo mode now delivers 358 percent faster page loads than when in normal load when the turbo is turned up to x3 (BetaNews failed to mention what test they used).  This is 58 percent more than even Opera's advertised boost.  The compressed pages are delivered with JPGs at high compression rates, making some images more pixellated.

We did our own testing of Opera 10.0 RC and looked at how it squared up against another recent testing-phase browser -- Google Chrome 4.  We tested the two browsers using FutureMark's PeaceKeeper browser test, which is now out of beta.  We also used CelticKane's JavaScript test to look at script performance in a bit more detail.  All tests were ran in Windows Vista on a VAIO notebook with T8100 (2.1 GHz, 45 nm) processor and a NVIDIA 8400 GS graphics card.  For Opera the Build was 1733, and Presto was 2.2.15.  For Chrome, the version was 4.0.202.0.

In PeaceKeeper Opera scored 1718 points.  This seems a bit low, compared to Safari and Chrome, but its partly because of the slower processor on the testing laptop.  However, Chrome did score 2929 points, easily besting Opera's offering.  Part of this is because the PeaceKeeper test does not test or reward for special/experimental standards such as Nav Links, Web Forms 2.0,VoiceXML/X+V, or CSS Projection mode (all of which Opera supports, but Google does not).  Such standards are still rarely used, though, so this may be a fair omission.

Digging a bit deeper we ran the two browsers through CelticKane's Javascript test.  Opera scored a modest 274 ms -- pretty good compared to the results listed on the page (faster than Chrome 2 was in July).  Still Chrome 4 managed to once again show up the competitor in speed, coming in at a smoking 195 ms (Apple's Safari is still faster, according to CelticKane's page).

In short Opera does not have an answer to Chrome in script performance in 10.0 RC.  It does have one potential answer in the long run -- its new Carakan Javascript engine -- but unfortunately it won't be available at 10.0's release.  Opera spokesman, Thomas Ford describes, "It won't be ready for (Opera) 10 final, but rest assured that it will be impressive when it comes."

In the meantime, it's important to consider the browsers' other features (besides pure speed).  Both Chrome and Opera suffer from being minority players in the market, so some pages that are poorly coded may not be compatible fully with them (but are compatible with Firefox/IE).  In general both offer fairly robust ad-filtering, pop-up blocking, and script filtering.  Both also include anti-phishing technologies.  Overall, Chrome is a bit more secure as each tab is sandboxed separately.  However, in our experience Opera does a better job of blocking most ads then Chrome.

So in speed Chrome 4 wins, and in security its a virtual draw.  So let's move to the bonus round -- what really sticks out about the browser.  Looking at Chrome first, one great feature is the tab isolation, which means that if one tab crashes the whole browser doesn't go down.  The privacy mode (incognito) is also nice.  Downsides include a slightly less refined interface and no tabbed colorization (a nice feature in IE). 

Looking at Opera 10.0 RC one impressive aspect is its friendly user interface.  Speed dial is a great feature and is implemented arguably better than the knock-offs (Firefox add-ons, etc.) that have arisen, since it was first revealed.  For users with slow connections Opera is the best option hands down, thanks to its turbo mode.  Opera also installs much faster than Chrome.  After clicking through the dialogs, Opera installed on our machine in 58 sec., while Chrome took close to 4 minutes -- Chrome's installation speed will be quicker than this on faster connections, though.  Disappointments include its lack of a privacy mode, poor plug-in/add-on support (though improving), and no tabbed colorization by default.

Our conclusion is that when it comes to speed Chrome beats Opera handily.  However, when features and other considerations come into play, the browsers are much closer and which is best boils down to personal preference.  We suggest you try both.  Opera 10.0 RC can be found here and Google Chrome 4 can be found here.