I have been looking into the available modules and Cinterion and Telit modules seem to fit the bill in case any other readers are have a similar problem to mine. I have also looked into Huawei modules but I was not impressed with the service offered by the distributor in my location unfortunately. I therefore gave it up altogether. If one cannot trust the reliability of a distributor's service at the information gathering stage, I don't think it's worth risking a project with that distributor and vendor at all.
Telit modules are slightly cheaper than Cinterion modules. However, I found out that for mass deployments, Cinterion modules seem to be superior. Out of 100,000 units deployed on a few projects, none of the modules have been returned to the vendor so far.
Both vendors provide a good support during the design phase of your M2M project as well, which is really useful if you are planning to develop your own hardware like myself.
In terms of size, Telit is slightly better than Cinterion but this difference is negligible from what I have discovered.
I will add further information as ı go along for the benefit of other readers.
I know your post is a bit old and maybe you have already decided on the module that you are going to use in your M2M design. We are the Authorized Telit GSM/GPS/3G/RF Modules Distributor for Turkiye , Syria , Iraq ,Iran, Saudi Arabia , Jordan ,Egypt ,UAE, Lebanon. So we are following more projects and also giving a design support. You can visit us from www.lte.com.tr.
If you can contact with us we can offer you suitable price for your projects.