mass update text in posts, pages, widgets – find and replace

hi – we’ve recently updated some of our messaging on our site, and there are a bunch of key phrases that we need to change throughout our wp site. what is the best way to do a mass find & replace for certain text in wp posts, pages, and widgets? would this be a matter of exporting the database, find & replace, and then uploading & replacing? I’m a little sketchy on this method – I’m worried if something goes wrong it could hose my installation. is there another way?

thanks!!