In my experience, I use Foxit Reader for more 2 years and this is free, very fast,and good software, for sure if you want promote it, you should pay, but with me, the free version is enough.
And if you want convert from MS Office, MS Project, and ... to PDF file for easy to email, you can try CutePDF also. It is free and really well, I do not have any trouble with it, it create the PDF file faster Adobe software more times.
So you can save some your time, your money, and free some memory for your computer ;).
Follow me on twitter :http://www.twitter.com/hrelax