Leasing is only good (IMO) when you're earning a decent income, don't want Johnny pocket too much of your not-so-loose change and wants a decent car. If you're using leasing for tax purposes, gotta take a note you really have to drive a lot of km's in order to reap the rewards.
One of my cars are on leasing thru CBFC and must travel over 25k km a year before I am ahead of Johnny. Your situation could be different though...also one thing, depending on who you work for, they might not use Prosperion. My company just won't deal with them at all but only with CBFC.