KeyJNote/Impressive experience

Agreed. I've also used KeyJNote for presentations (in fact, I didn't know until this moment that is was renamed, I thought it had been abandoned since the old page keyjnote.sf.net has been dead for a long time).

Usually I turn off the transitions though, or make them really quick and unobtrusive. The reason I like keyjnote is the ease of navigation (overview mode, and also single-key custom bookmarks). I find it quite jarring when a presenter has to quick-flip through ten or more slides to get back to some graph, and then forward again, often overshooting a bit.