[Tim Brewer]

Killer,
These guys are right, it's just a standard wood saw. I don't believe there is any such thing as a "fiberglass only" saw. What I do is (1) use tape, (2) use a smaller than you need holesaw, and then use my moto-tool with a course rotery sand paper drum and reem out to the size needed. That moto-tool will cut through fiberglass like no other tool can.
Good luck,
Tim