The 180/f2.8 AFD is almost as long, is just as fast in aperture, but weighs half as much, is two full inches shorter, is slightly smaller in diameter - and costs about a half as much as a 70-200/f2.8 AFS VR-I ($1500 used) and less than a third as much as a 70-200/f2.8 AFS VR-II ($2400 new). It also outperforms either of them, optically. The hood is even built-in.
In exchange, it has slower focusing, isn't a zoom, and has no focus limiter. And no VR. As a screwdriver AF lens, it doesn't AF on D3100/5100 bodies.
I got mine for about $500, obviously used. I use it when I want to go light but probably need f/2.8, and it serves that purpose very well.
_____ Brian... a bicoastal Nikonian and Team Member
My gallery is online. Comments and critique welcomed any time!