Here's the video of our hands-on with Opera Mobile 9.5 Beta. As promised, we tested in a Sprint Mogul. We left it stock, no memory optimizations on it, to try to get a good feel of how big a memory hog Opera Mobile would be. Verdict: it's pretty darn greedy, but even so it seems to run pretty well. Here's to hoping that this is a 'beta' issue. Co-WMExpert Phil Nickinson also writes in about Opera:

Runs pretty well on my trusty 750 (even with EDGE only), but HOLY MEMORY HOG BATMAN! Might wanna suggest this, too, to move the cache to the storage card...
  • Close Opera.
  • Create a folder on your storage card where the cache files will go.* I chose \Storage Card\Program Files\Opera\cache4, but I don't think the folder structure or folder name matter.
  • Open \Application Data\Opera\opera.ini in a text editor.
  • In the [User Prefs] section, add the following line: Cache Directory4=[full path to folder on storage card].
  • Save and close opera.ini.
  • Restart Opera. Your cache is now being written to your storage card.

...While that might not get rid of the persistent memory errors, at least it will free up some ROM space for ya.

How's Opera performing for you?

Update: Jeff Kirvin notes his impressions in the comments and lets us know that the reason flash didn't work in our video above is that it's currently disabled in this beta; ditto ActiveX.