PDF Suite

I was trying to find a Substitute for Adobe Acrobat so that my PDF can be viewed , edited and conversion from anyother doc to PDF can take place.
Came across a nice application called PDF Suite .
Nice application. This has met most of the expectation especially in the area of converting to PDF. Has been working fine for viewing and editing as well, but recently I have started facing problem for viewing secured documents and newly created documents especially the ones I receive in E-Mail from Vodafone Etc. The Application exits saying the document is not compatible . i have been checking for updates in the application but none are available .
If someone comes across any software having the similar capabilities do let me know.