Lens advice sought

[jupiter618]

Hi guys, I'm new to the forum and still have a lot to learn. I need some advice on lenses and what follows is my predicament described;

I recently got a D7000, and have the following lenses;

micro nikkor AF-S 105mm f/2.8 VR (my pride and joy)
Nikon AF 70-300mm 1:4-5.6 G
Nikon AF 18-105mm f/3.5-5.6 VR

In May we are going on a trip to visit Mt. Lamington National Park, World Heritage area of legendary beauty and I'd really like to have the kit to do it justice. The dilemma is that I've blown my photography budget pretty much for the next 6 months. I can't afford to buy an expensive lens at the moment. However, I've been reading that the cheap little "kit" lens, the 18-55mm VR, is actually very good optically giving good sharp pictures. You can buy these new for around $100 which is absolute peanuts! My question is; would the 18-55 be noticeably better than my mediocre 18-105? Is it worth buying the 18-55 as a general purpose zoom for this trip? I also read that it focuses at 11.5cm from the front of the lens giving quite decent macro capabilities. I'm getting most of my info from here -*removed : see site rules 3-7: admin*
Comments? Suggestions?