As far as performance, I found Shiira to be very solid. It loaded pages of all kinds, rendered Flash animation with no problems, and even beat out Safari and Firefox in terms of rendering speed on a couple of pages (albeit not by a particularly noteworthy margin). The browser was also very stable. All of this is important because, bells and whistles aside, the most important piece of a browser to me is that it can actually surf the Web painlessly and quickly.
Unfortunately, I did see some unfinished aspects of this open source browser. Some of Shiira's preference options seemed unfinished. For example, the RSS feed preferences pane refused to open at all (even so, the built-in RSS reader functioned fairly well -- though being used to full featured stand-alone RSS readers, I'm not sure it would be my first choice). In addition, the pane in the preferences dialog called Key Mappings, which should allow users to assign keyboard shortcuts to menu items, does not seem to be implemented yet (though I was able to open the pane itself).
Even so, the combination of good features, Apple-inspired interface and overall performance left me convinced that, with a little more development, Shiira could easily give other Mac browsers a run for their money. Without a doubt, Shiira is definitely worth a look, but be prepared to spend a little time getting used to its interface.
-- Ryan Faas
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