300mm lense

[size13]

I'm after a 300mm lense for my D70 for < £400.
Main use will be outside taking pictures of boats, so may be moving fast - usually not!

I'm looking at (number in bracket is score from fm reviews):

Sigma 28-300mm F3.5-6.3 Aspherical Macro - not good reviews (5.9)
Sigma 70-300mm F4-5.6 APO Macro Super DG
Tamron AF 28-300mm XR Di LD Aspherical Macro IF f3.5-6.3 (8)
AF Zoom-Nikkor 70-300mm f/4-5.6G or AF Zoom-Nikkor 70-300mm f/4-5.6D ED

[size13]

What's the difference between that and the 2 nikons I've listed?

I'm a bit new to lenses!

>> Edited by size13 on Thursday 2nd June 12:21

[size13]

Oh, I thought you were talking about the 70-300mm f/4-5.6D AF ED Zoom-Nikkor boxed

A bit of range would be best - I didn't mean prime in my original post - sorry

[size13]

What's the difference between the Nikkor G, and D ED?

According to Ken Rockwell...

"It ought to be similar to the 70-300mm f/4-5.6D ED AF since I suspect it has the same optics. This G lens has sloppier mechanics and a plastic mount; the three times as expensive ED version has a metal mount. I suspect the glass is the same on both but haven't actually shot them head-to head to confirm."

>> Edited by size13 on Thursday 2nd June 12:32

[size13]

Anybody tried the new Tamron 18-200mm f/3.5-6.3 XR Di II?