Dynamics NAV 2013 - Which client to choose?

Hi All!

I`m Pedro. 

In our group of entreprise, we work with a Dynamics NAV 2009 R2 hosted. I acess in firms with Windows terminal server, and we have 70 users. Each firm have a development specific for the others firms.

We have in hosting a Microsoft Sharepoint Server 2010. We will upgrade to 2013.

But in NAV what version we choose?

a)     Microsoft Dynamics Nav Web Client

b)     Microsoft Dynamics Portal Framework

c)      Or we can work in some users with web client and the others users Portal Framework

And the feature limitations?

Or upgrade to NAV 2009 RTC first?

Thanks,

Pedro Monteiro