If you have a GUARANTEED six-figure salary waiting for you, then take my advice and WAIT. You can skip the 335i and just buy yourself an F80 M3. My advice for now, assuming you have that guaranteed six-figure salary, is to sell your truck and buy something reasonable to drive for three years (maybe a Nissan 350Z if you want something sporty and fun; they can be had for ~$10,000).
Let's say you do buy that car because, "Damn... that's an awesome car. All I want is an awesome, nice car." Yeah... I always say the same thing. I always get so close to buying an E92 335i or an E46 M3 time and time again, but then I sit down and REALLY think about it.
"What if I wreck it?" Yup. It happens. If you're making payments, you'll be left in the hole. You MIGHT get a couple grand out of the situation, depending on how much you put down on the car and how much you've paid off, but you won't have your car anymore AND you'll be out all that money.
"I'll pay it off before six years!" So... what? Four years? That's still a LONG time to be giving people your money.
Trust me. I've been there, done that. I bought a 2003 Mustang GT when I was 20 years old because, "Aw, man! I KNOW I can afford those payments for 60 months!"
One month later, a girl with her face buried in her phone made me crash into a concrete wall and she just kept driving. I managed to get $2,500 out of that payoff. I said, "Screw paying long term payments" and put that $2,500 down on a $6,000 car. I paid it off in a year. I realized that's when having no payment is the way to go, even if you know you can afford it.
I hope I'm making sense to you.