best GPRS/GSM Shield

I am building a car alarm that can send/receive text but not sure what shield to get. Am going to use (I think so far)T-MOBILE it looks like the cheapest in pennsylvania

You ask in the title for the best, and in your post it seems you are looking for the cheapest. So can you clarify your needs a bit more?

Furthermore I didn't know that T-mobile makes GSM shields....

  • sparkfun do sell them I know, and they have pretty good support -

The best to use and cheaper is better, t-mobile will be the cellular carrier

Can you define best?

What I find best does not necessary be the same what you find the best ...

What shield do you think that is cheep and will do the job

and will do the job

What is the job? Windshield scraper and cell modem might both be potential uses.

I am building a car alarm that will text me if the door is opened and I can send text to turn alarm off or on. I am using arduino uno but not sure what cellular shield I should use. I was looking at using t mobile sim card
I hope this explain it better