Help with Unicel - Anyone?

My son and I have the unlimited plan through Unicel.  We have unlimited minutes, text messages, and long distance for a set price.  Great deal.  Except for one thing.  It doesn't allow roaming.  When my son's phone roams, it goes to Unicel Plus, which won't work with our plan. 

So here's my problem:  He has a Razr, and it goes to Unicel Plus at least 50% of the time.  I have an old refurbished Nokia, and mine hardly ever goes to Unicel Plus.  In fact a few times we've stood side by side, me with a signal and him with Unicel Plus.

Of course silly me signed a contract to get the Razr through Unicel.  Now they're telling me I'll have to pay for a new phone and they can't guarantee it'll work all the time on his plan.  They won't let me out of the contract.

He's only had the phone for 6 months, and we've been fighting with them the whole time.  The most satisfaction we got was twice they suggested replacing the sim card.  Didn't work.

Now don't go suggesting I get him an old refurbished Nokia, heaven forbid!  He has a rep to maintain after all. 

Is there any hope?  Ideas, suggestions anyone?