Yes, MET is definitely a "no regrets" kind of pin to buy, whether used or NIB. If you keep pins for a while, buying NIB isn't so bad because you get the play value out of it. I think of dropping $1 for every play, especially in games like GB, and having one at home to enjoy makes sense. Of course, my pins all have high # of plays since I have been hosting monthly tournaments for the past 4 years (constant maintenance and nobody can tell my Tron has thousands of plays on it).
Best advice I can offer is that if you want the game, and are comfortable with the price, just get it and enjoy....