I've been using Foxit Reader instead of Acrobat for over a year, and I must say that I am generally very pleased with it. I really love it - it's fast (way faster than Acrobat), relatively low memory footprint, supports all PFD files I read (there were some issues with the previous version but the new one really works like a charm) and doesn't even require installation.
A few days ago I wanted to use their PDF printer add-on. Never mind the fact that it didn't work and got completely stuck - I managed without it in the end. But today I wanted to print something from Outlook, and guess what - they automatically replaced my default printer to be the Foxit PDF Printer!!!
Now THAT's something that can make me really HATE, otherwise EXCELLENT software!!!