Changing out RED antifreeze
 

I have a 2001 STS with the red antifreeze in it (DexCool?). I'm going to a rad shop tomorrow for a flush, and have a few questions:

1. Should I have them replace the rad with Dexcool? Or a generic Long-life antifreeze? (They said on the phone that the red stuff had lots of problems, and to switch it out)
2. They have a machine which evacuates the coolant. Should I insist the remove the lower rad house to get any junk out? Or is a machine evacuation good enough?

Thanks