So I heard the DAT is similar to the PCAT in terms of difficulty.
My library has PCAT review material, should I use that to gauge how I would do on the DAT?
I think that there is a free sample DAT test online from 2009. If you want to gauge the DAT, I would use actual DAT materials and not another healthcare profession's admissions material.
There are lots of resources available. There is no gauging, you need to prepare. There are strategies that are test specific. Start studying and just see how comfortable you are with the exam and material.