Hey guys, need some advice/suggestions from those that know more than me, yet again! After borrowing Mitchell's Nikon 300 F4 a few weeks ago, I had my mind made up that was the lens I was going to buy until I can afford the Nikon 300 2.8 VR. I would have had the F4 two weeks ago, but in my haste misread the calendar and how the checks fall. Well, today I received an unexpected check in the mail and Jen called me at work to drop the good news. While it's a nice amount, it's not enough to let me get the Nikon 300 2.8 VR. So my question is, do I go on as planned and get the 300 F/4 or should I get the Sigma 300 2.8 until I can afford the Nikon 300 2.8? Thanks in advance guys! I really need help making up my mind... I am going nuts thinking about this!