Looking for recommendations here.
Creating an automated regression test for a new Quotes application (extJs Web app).
Kinda between Rational Robot and Selenium at the moment on which to use....if we go with Selenium, can you recommend a free-ware automated tool that we could incorporate into the pack to provide us with a screenshot comparison test ?

As its a new app wed like to have this screenshot comparison functionality to stand over for test, but I dont think its built into Selenium IDE so need a free-ware tool.

I know Robot has this in-built but Robot seems to be having a couple of problems recording some of the fields so Selenium might have to be the way to go - So any recommendations will be greatly appreciated.