I'm from Grand Rapids.
My Nextel gets bad service in GR, but really good service when I'm at school in Mt. Pleasant. I used to have a Verizon back home in high school and it rocked, four bars pretty much anywhere.
Nextel has some cheap plans, I love their phones and most of my friends have them so I use the 2-way function a lot (unlimited and free included in my plan). But I wouldn't recommend it at GVSU. Last week I was at my buddy's apartment out there and I didn't get any service.