Depends entirely on what your expected use for the money is, even for a "young person." Also, as of the most recent fed meeting, rates are no longer continuously climbing (at least for now).Further, investing borrowed money (as is being discussed here) is leveraged investing - which, while it can multiply returns, also multiplies risk and has to be accounted for in any reasonable asset strategy.
I was just responding to Nick's sweeping seeming-condemnation of them.
Wait, you guys have cars? I've lived the impoverished life of a student for too long -- I've been living without a car for 4 years!