Contain seems slower than javascript based sites. Any idea why? If you leave the flash UI framework and do it all yourself is there a big performance hit?
A possible (and most common) reason for slowness is that the developers might have coded it such that all UI graphical assets required sitewide (buttons,icons and other graphical assets) are preloaded before the actual content starts rendering (rather than loading graphical assets on an, as-it-is-required basis).
Using generic flash frameworks and components definitely increase the file size as they usually come with a lot of functionality (thus code) and legacy code that you might never really use.So if time allows,building your own components is highly recommended to keep file sizes low.
It is possible to build real fast sites with Flash. As an example, if a page contains 20 small thumbnail images (means 20 separate http calls in an html environment), it is possible to load a single zip file with all 20 thumbs into flash and unzip and render it at runtime.Thus reducing the number of http calls from 20 to 1.
As lowdown commented above, the performance of a Flash app depends on how the developer approaches the problem.
As many other commenters pointed out, a 100% Flash based environment is definitely not a great choice for a social network site like Kontain. But the site's neat design and rendering is a great example to show that Flash sites neednt always be cheesy or flashy or flexy.
