Help me go lens shopping!

[summers_enemy]

Hello everyone!

I've had my D50 for about 8 months now, and to be honest I'm still not sure I like it. My images always seem too soft, no matter what lens I use or the settings I fiddle with on the camera. I welcome the day that I don't need to use unsharp mask before giving pictures to clients. :roll:

With that in mind, I've got the itch to buy a new lens. I've never been happy with the kit lens, nor am I really happy with my other Nikon lens. However, my big zoom Sigma is awesome, really pleased with that lens. So that's the brand I'm leaning towards for the new purchase to replace my kit lens.

I'm considering both of these:

24-135mm f/2.8-4.5 http://www.bhphotovideo.com/bnh/controller/home?O=productlist&A=details&Q=&sku=283382&is=REG&addedTroughType=categoryNavigation#

28-300m f/3.5-6.3 http://www.bhphotovideo.com/bnh/controller/home?O=productlist&A=details&Q=&sku=389309&is=REG&addedTroughType=categoryNavigation

I can't quite decide. I'm leaning towards the 28-300 just because it would be so much more versatile (it would eliminate the need for me to change lenses like I have to now using the supplied Nikon lens and my 70-300 Sigma zoom). However, I find the fastness of the first listed lens to be quite attractive as well.

Can anyone help me shop? Anyone own either of these lenses or have personal experience using them? Or, alternatively, can someone point me in the direction of a sharp lens for a Nikon D50 that is sub $400?

I currently have:

Nikon D50 w/kit lens (17-55 3.5/5.6 I think)
Nikon 50mm f/1.8
Sigma 70-300mm (4.5-5.6 I think)

Thanks so much for your help. It's greatly appreciated.

 

[summers_enemy]

I know it's a freakishly long post, but surely someone has thoughts?