I got prompted to upgrade my service to 3g 2100. I assume that I am currently on the 'legacy' service. I'm a bit confused as to why the change is not automatic if it is the same for mobile . Meaning, is is two separate companies or services (regular 3g and 3g 2100)? Is the voice any different? If they are the same from a billing or service perspective, is there any disadvantages to upgrading the service from legacy to 3g 2100?

I did the online and *570# check and I am 'pre-qualified' for the upgrade . I'm just a little nervous about switching.

I also wanted to do it for wife, which would give her a new base rate of 99 satang/min for all networks. She currently has 1.50 bt/min phone if she doesn't use any of the other temporary promotions (mao mao).

In Chumphon Town.

AWN is a subsidiary of AIS; this is required to track auction revenue from concession revenue.

The GSM 900 concession will end in 2015 so eventually you'll have to change,

If you want/need 2100 MHz 3G then you should change. If you are fully satisfied now, then maybe no hurry to change.

I can't think of any disadvantages except maybe different expiration/validity dates.

Maybe switch you or your wife first, see how things are then decide on the second number?