Sigma 18-50mm f/2.8-4.5 vs. Canon or Nikon kit lens

[Chitoneus]

Has anyone had experience with the Sigma 18-50mm f/2.8-4.5 (not to be confused with the 18-50mm f/2.8 lens)? I'm replacing my Rebel XTi with either a Rebel T1i or a Nikon D5000, and I'm wondering if this would be an upgrade over either kit lens. I have only found one detailed technical review of it:

http://www.slrgear.com/reviews/showproduct.php/product/1249/cat/31

But I'd like to know if anyone has any practical experience with it, and if so, what kind of shots you've taken with it.

Long story short, this was not a planned upgrade, so I'm not looking to spend a whole lot. I'm almost tempted to just get a 24 or 28mm prime lens, since that's about the range I would generally use with the Canon kit lens, but I'm afraid I'd end up missing the versatility of a zoom lens. So perhaps a better question is:

What is a good multi-purpose lens for around $300?

 

[Phrasikleia]

I'd recommend the Tamron 17-50mm f/2.8 (non-VC version). It has superb optics, nice build quality, and even has a zoom lock (which is a really nice feature for a walk-around lens). You can find them used for about $350 or even a bit less. It's an extraordinarily sharp lens, and the constant f/2.8 makes it very capable and very fun to use.

 

[toxic]

I didn't even know that existed...but I'm be skeptical of OS and HSM for $200. I'd save up for a Tamron 17-50 f/2.8 or Sigma 18-50 f/2.8 Macro instead. both should be around $300 used.

you could always just buy it and return it if you don't like it.