I love my phone, but honestly, I wouldn't pay $150 for a used one. Assuming you're referencing the XT912 or XT910, it's almost 3 years old and there are better phones out there. If you're willing to wait a little longer, the Moto X will probably drop in price again once the new rumored model, X+1, is out
Have to say I love my RAZR. Its the first droid smart phone I have ever owned and I'm quite content with it. Granted there are much more powerful phones on the market now. But $150 for a used xt910 or xt912 seems unreasonably high in price.