It also already monitors oil pressure, but apparently Pontiac didn't want to put it on your dash. I forgot that for a second too, since my car came with an oil pressure gauge.
I think it's worth every penny.
If you don't want oil pressure for some reason, I have fuel pressure and find it handy. Doesn't move a whole lot while driving, and rises when you stomp on it, but it is a definite warning to a failing pump if it decides to go while I'm being rough with it.