If you've got the space and money, get one. Just make sure you use proper form when doing bag work and if you feel you're doing something wrong, stop! Stop! Stop!
Check with your trainer afterwards. The worst thing you could do is develope bad habits regarding form.
I think it would be great for conditioning the fists and shins, as well as strenghting the wrists and developing power. Be careful not to go all out on it when you first use it to avoid injuries. A sprained or broken wrist is no fun at all.
Also, if you're planning on hitting it hard, wrap your hands and wear bag gloves. Your hands will love you for it once you're hitting your 50's.
Once again, have fun.