Ain't lagging, true is that more than 150MB RAM free is needed for current Opera Mobile or Chrome. Btw, Maxthon sucks running on ICS, same player format can be found on Dolphin browser being based on Fennec design.
With root access you can copy your Speed Dial (favorites.db) from the PC Opera profile manually to your phone (/data/data/com.opera.browser/app_opera/). I guess that even if you move the passwords file (Login Data) it won't work but you may try it. Only do that if you understand what you're doing.
Key popup set on no delay in keyboard settings can modify URL bar behavior. Current URL isn't shown when is corrected (i.e. gogle.com > google.com) before page loading (3g connection) even at reload. Browsers with similar behavior = none. NexusS running ICS with animation set on 0,5 if that counts. Beta2 does the same.