Well, after some research, I decided to go with the Viair 300P. Its affordable, the reviews are excellent, and fits perfectly in the engine bay. The included hose is 25ft, and the accessories included are great. It was a pretty simple choice after seeing the reviews, actually, and a lot of people actually preferred Viair over ARB. I am not installing tanks or switches in the cockpit, I just want it simple.
Its going to be hard mounted, so nobody can "borrow" it, and I wont leave it at home, sitting in the bag. Now all I have to do is find or make a cover for it, that can stay snugged up around it, when I'm not using it.