Just installed on a WM6.1 Palm Treo Pro device.
- Install fails if you download to storage card and try to install, however download to main memory and install to either main memory or storage card and you're fine
- Upon startup, it calls the UK a "non-supported region" as yet
- It's pretty quick to start up and pages pull down with a good speed over the HSxPA connection on the Treo Pro
- Using the square 240x240 screen format was no problem
However - all this said, it's a very basic browser, sure it handles a lot of "stuff" on the web, but you always start with a page overview zoomed out and have to zoom into the bits you want and there's no menu option to create a "striped page" optimised for the screen size you're on, ala Opera. There's no way I want to keep zooming in, out and moving a virtual mouse pointer round a screen, whilst on the move, using my device one handed - all I want to do is just scroll down or up using the d-pad on the device.
So quick first impressions - it's quick, very few options/configurations, handles lots of web content and is light on memory (1.6MB) - but it's no excuse to uninstall Opera 8.65 from your device.