MetroPCS Flashed Touch Pro (Juggalo's ROM) Question

[rootdude]

Hi Folks -

Thanks for letting me jump in on the party...

I just bought a Touch Pro, flashed for MetroPCS using Juggalo's ROM (it seems), and I wanted to do a little ROM experimentation. If I flash another ROM, will I end up wiping out the MetroPCS programming that has been done to my handset? If so, what would I need to do following the installation of a new ROM to make sure I could still use my Touch Pro on MetroPCS?

I know it's kind of a newb question, but this is my first foray into the CDMA world - I've been flashing GSM PPC handsets for ages.

TIA,
RootDude