Zoom with IS -24-105 vs new 24-70 f4?

[eco_bach]

I really need a good zoom with IS as my next purchase for hand held run n gun.
With the amazing prices on the older 24-105 was considering it as first choice.
A very popular lens. Was one of the principal pieces of glass used on a cinematography award winning doco I caught recently, E-Team.
http://www.indiewire.com/article/ho...-gives-an-insiders-look-on-filming-war-crimes

I've also borrowed it from a co-worker and found the still images to be exceptionally sharp.

However, after some research I've discovered it DOES have its problems
-strong vignetting wide open
-strong distortion wide open

Now there is a new kid on the block, the new 24-70 f4 IS.
I've read mixed reports online, some saying that it is slightly softer and lower contrast overall compared to the 24-105, but one review site I trust says it is
1-overall sharper than the 24-105 all focal lengths
2-almost distortion free
3-has better IS
http://www.lensrentals.com/blog/2013/01/canon-24-70-f4-is-resolution-tests

But is it worth the extra $500 over the 24-105? What has been your experience?

 

[egproductions]

Another option for you would be the Sigma 24-105 art lens. It's optically better than the canon, cheaper when bought new, better IS, and a beautiful finish as are all the art lenses.

http://www.amazon.com/Sigma-635101-24-105mm-Canon-Cameras/dp/B00G6K4XZG/ref=sr_1_1?ie=UTF8&qid=1399405803&sr=8-1&keywords=sigma+24-105

 

[New_Zealand]

I was thinking about getting the 24-70 after filming with my 50mm. There were a number of places I wish I had a wider lens and also taking photos in the Aussie Outback I wish I had a Zoom. I have the 70 200 is ii but left it in NZ due to the weight of the lens and the fact of traveling and staying at Backpackers I didn't want to take a chance of it getting lost. But there were times I really wish I had it so that is where the thought of getting a 24-70. Much easier to carry (I think????)

 

[eco_bach]

It's optically better than the canon,

Thanks.
Which Canon?
Can you point me to any reviews?
Price wise, really about the same as the 24-105

Also, most Canon L glass generally holds its resale value quite well

 

[egproductions]

Thanks.
Which Canon?

I was comparing the canon 24-105 with the sigma 24-105. The Canon 24-70 will probably beat both out but the sigma is a better choice than the canon 24-105. There are plenty of reviews out there comparing the two 24-105s even though the sigma is brand new and the canon is more than 12 years old.

The sigma art line will hold its value well...they are quickly making believers out of everyone. In comparison the used market is flooded wuth Canon 24-105s, you can pick one up for significantly less than its retail price. If you buy it retail, don't expect to get that back.