Am I getting out-of-control with buying equipment?

Question

I started getting serious about photography two years ago before heading to Iceland for a trip. I bought a D40 and a Tokina wide-angle for landscapes for a total cost of about $900.

I got some decent shots. For example,

Over the past two years I've added a Sigma 70-300mm 4.6f at about $250 and a Nikon 50mm 1.8f for about $225. Still getting some good shots including these from last month:

Tokina:

Sigma:

Nikon:

In November, I'm taking a trip to Africa and am considering upgrading. Right now, I'm sitting on the fence between upgrading the body to a Nikon D700 or keeping the D40 and getting a 300mm f/2.8 VRII. Either one of those options means spending as much or more on upgrading gear than on the trip itself.

So my question is, as a hobbyist with some semi-pro aspirations and a desire to enter serious amateur competitions, am I getting out of control with buying gear too early, or should I just keep getting better with what I have right now? Primarily, I just love taking photos. Making money and entering contests will always be secondary. I just wonder with where I am in my current abilities if so much money going into gear will bring an equivalent amount of satisfaction from something that I'm not really doing for the money or notoriety.

Answer

I like gear. If you can afford it, why not. But better gear doesn't necessarily make better pictures.

If you're going on an African safari, that's one place where a good tele is really required. But you should be able to rent one, or possibly buy a used one from someone like KEH and return it after the trip, if you don't think it would get much use afterwards.

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