I can't say I've had it yet but I recently saw there's a cookbook out there on the stuff. I haven't had Pork Roll either but I have had Vienna Sausages and thought that maybe SPAM was close.
When I was younger, I did work for 3 months at Silgan Containers out in the Valley out here and they manufactured the SPAM can. So cool!
For your next trip to Hawaii, even McDonald's has it on the menu!