Traveling Internationally info please

Well, tomorrow Im going down to Mexico and obviously Im taking my blackberry with me. I have a couple questions and am looking for input on a couple things.

1. Im on Tmobile and I can add the Blackberry International plan for just the weekend while Im there and I have considered doing that. However, Im not sure I even really need it besides the fact that it would be cool to have and test out while im there. Its not life and death if I dont get emails for the weekend.

2. So, I have considered just turning off the data while Im there and leaving it like that. But I read somewhere that regardless of what sim you have in your phone that the email will still come through because its read your phone pin and not the sim you have in there. Is this true?

Any additional advice on using my blackberry out of the country?

i turned off data services and used a local sim card.
but heck if youre just going to mexico for the weekend just turn off the antenna (assuming you dont need to make calls) and enjoy yourself
*as much as you can enjoy yourself w/o data*