Yeah, you can always just buy one tire to test it out. Or you could try a bit of each - buy one Armadillo tire and one Tire Liner and try them both, one on each wheel.

But personally, I'd go with the Armadillo's. I've heard to many people say they didn't quite install their tire liner right and the tire liner itself ended up puncturing their tube and causing a flat. Ride quality is also affected by the liner, though I don't know if it's more than the Armadillo or not. And for the liner to work, something would first puncture the entire tire than be stopped by the liner, whereas with the Armadillo it only gets about halfway through the tire before being stopped.

Also, the other posters are right - perhaps there's something wrong with your pump, but while letting the air pressure down to 80 shouldn't hurt anything none of the rest of us have to do that. fyi.