Thank you for all the suggestions and responses, it's very helpful.

In my personal opinion, I prefer to have 3G because:

- I can have a spare SIM that can receive messages, extremely useful when I am living in China: As almost everything in China now requires a phone number to register(in order to spam you). So I have a separate number just for registering take away/banking/other spam services, and keep my main number free of (most) junks. With a 3G on board I can then do everything in one device. Not the same case in England though.

- I feel more "complete" with the 3G modem on board. As this device was designed back in its time, we reserved the space for 3G and the original ID has two slots on the side, just feel more "complete" with everything.

I do concern the SW and battery (also software) though. However, in theory the 3G version should be compatible with the current SW (with the 3G bit missing), and maybe can manually add the missing bit. But I agree, don't want to cause more flux which result to a delay.

So in conclusion, we will check if adding 3G will cause extra cost or delays then decide. Make the device hitting market is the first priority.