IMessage on Edge/2G Network?

I just bought an iphone 4.It was originally on AT&T but i unlocked it and now it is on the t-mobile network. I talked to t-mobile and they said that since it is not a t-mobile device, it does not have the bandwidth to support the 3g/4g network. Aright, well crap. I can get over this however, since this is only a temporary phone. My question is me and my friends have a lot of group messages on IMessage. Will i still be able to receive these messages if i have Edge or 2g? I know it works on Wi-Fi, but what if i have no Wi-Fi access. Will i still receive these group messages?

Added (1). Also, can i SEND imessages? Every time i try to it just sends a text. Does that mean that every single person in the group chat receives an individual text message? Or does it still go to the group chat

Added (2). Also, can i SEND imessages? Every time i try to it just sends a text. Does that mean that every single person in the group chat receives an individual text message? Or does it still go to the group chat

Yes you will. Wi-Fi is way faster and on 2g you will Likely be frustrated because of the slowness. Just be patient and you should be fine.

You should, but it would take a while to receive since 2G is much slower than 3G.