A buddy of mine works for bmw corp and I had the pleasure of driving in a yet unreleased M6 and all i can say is WOW, I can see old rich guys wrapping their 120k beauty around poles in the near future. Talk about *****, the car is simply amazing to say the least. 330i is ok, I am biased of course but I dont see a car out under $50k I would like over my g.

 

Ok guys, first of all the G35 is a great car, but it is no Porsche where we can say ok,hands down, never BMW. I can assure you that at least half of you that said hell no....if had the money or chance, would in fact get one after driving one. No, the 330i is not as fast as the G35 (about 1/2sec 0-60, which is still a lot), but would prob take one on the track where higher speeds and curves are involved. I had a 2006 330i 6mt, premium,sport,nav,cold pkg. which I picked up from the factory in Germany, as I wanted it custom ordered. I then drove it for about 1000 miles on the autobahns in Germany before shipping it back to the US, and all I can say is this is one amazing machine. It might not look like much, nor the specs sounds too great, but as soon as you go above 100mph, you'll see the difference between what makes a BMW so great. While I was there I normally cruised at about 140mph, and topped out at 155mph. The steering get a little loose after 148ish, or so, but the car never feels upset, as opposed to the G, after 120.
Unfortunately, some kid in a lexus one block from my house blew a stop sign and totalled it!! I about 4k in depriciation, and could not afford another new one, and there is no other one in the country like mine optioned the same way mine was. Before I got the 330 i was going to buy the G, but a bad experience at the dealer threw me off. So in the end, I got the G, and it is a fantastic car.....great power, great brakes, and amazing looks on the outside. However the interior quality is depressing and feels very cheap, but the power makes up for it.
I would keep your G35, as it is a good car, run it to the ground and save up so when you have to get a new car, you can get a new loaded and customized the way you want 330, or 335....which is going to set you back about 44k msrp....and then do the European delivery option!!
Here are some vids that we took while picking up the car in Germany and driving on the autobahn. This, I believe, I every car guys dream.

Doing 120-150mph...good quality:
http://video.google.com/videoplay?docid=-2681289322087062445
Going 155mph, and hitting the limiter....bad quality:
http://video.google.com/videoplay?docid=-1334267766750839818