Network Transition

I am been asked to transition our current 128kb ISDN network to a 500kb Satellite network. I?ve researched the company and they do not support a network connection. Only a single user anything larger would be on our hands. We are 25 strong and getting larger. I found that the ISDN with router is working better then a 500kb using Wingate or another proxy server. Any help out there on this?

Do they make a Satellite routers?