A properly designed Open-AT application never faces any risk of causing the module to freeze. The proper way to create an Open-AT application is to first execute it in debug mode (where it utilizes the resources of the PC) and check out any of the potential problems.
Only then the application should be created for the target mode and downloaded in the modem.
Also, Wavecom modules have inbuilt watchdog mechanism and RTK which restarts the module in case the application performs some invalid task (like infinite loop or invalid pointer operation). The best way to design an Open-AT application is to subscribe to a custom AT command (like AT+START) and when this command is given, the functionalities provided in the application will come into picture. In this way, even in case of faults in the application, the module will reset and you can erase the application or download a new application. (This is because, you have to give AT+START command to start the application and if there is some problem in application, the module will restart. Hence, don’t give AT+START but just erase the application using AT+WOPEN=0 and then AT+WOPEN=4).
Please note here that AT+START command is not used here to start/stop the Open-AT application itself. It is rather used to control the functionalities that your application provides. For instance, you start your Open-AT application and only when you give AT+START will it connect to the web server etc.
In case, you are using your application for a real M2M scenario where there is no entity to give such command, you can subscribe to a timer and when the timer expires, you start the functionalities provided by the application. In this case, if you application fails (crashes), the module will reset. Now, as you have provided the application’s functionality in the timer handler function, you can always stop the application before the timer expires and you application starts. Hence, there is no risk in this case too.
So, by and large, there is no problem in using Wavecom products. According to my experience, I have found Wavecom products to be the best in the market.
Rest depends upon your perception.
Open AT Fan.