It's definitely a good idea to use first aid, not because the test challenges your medical skills or knowledge (it doesn't), but because not understanding the test format and expected questions etc would cause you to lose a lot of points. The test is nothing like a real clinical encounter, but you have to go through the motions and do things the way (and exactly the way) they expect you to do them. Ie, ask for sexual/drug/alcohol history no matter what the chief complaint is, ask specific questions containing the exact keyword that will make the patient tell you what you have to know etc. Unlike with real patients, open-ended questions will get you NOWHERE with some (or even most) SPs.