What kind of switch should I use if I’m getting a T1 line installed?

We currently have a 10/100Base-T 48-port switch for a DSL connection. We are getting a T1 line installed and I have been asked if a GigE switch would be better for our faster network. What do your great minds suggest? I thought that since the connection is 1.54Mbps, not 1000Mbps, that what we have should be sufficient. What do you think?