Wanting to buy an AMG Mercedes... Not sure if I should.'

Go for it. Your life will never be the same. Enjoy it now I say. I just decided last week I am going to buy a New Mercedes 550 4matic. First though I am buying a used one for $40K and then move up in 2 years. I drove over 20,000 miles in a Mercedes driving my Father to his Winter homes. Back and Forth. Back and Forth. You could have a 1000 mile day and step out of this amazing technologically advanced machine and feel like a million bucks. It does so many things. And it feels amazing driving it. Sorry for the rant. Just give yourself permission and say yes. Once you do, you'll wonder why you waited so long.