Requesting assistance from experienced EF-S lens owners

jwb1 wrote:

Hello all. Thank you for taking the time. I promise I googled this question before posting...

I have a T4i with the 18-55 STM. I love this lens but I want to upgrade to something that is better (useability, IQ). I primarily shoot stills, but I do like to shoot videos to document trips (casual use). I am trying not to focus on lens weight and build quality so much.

The lenses I am looking at are

Canon 18-135 f/3.5-5.6 STM. Less than $300 new on ebay. I would sell 18-55 STM if purchased.

Canon 55-250 f/4-5.6 STM. Less than $200 new on ebay. I would keep 18-55 STM if purchased.

Sigma 17-70 f/2.8-4 "C" (the updated version). Less than $400 new on ebay. I would sell 18-55 STM if purchased.

I am leaning towards the 18-135 STM because it will let me use one lens. But since it is a superzoom, is there noticeable falloff in IQ compared to the 18-55 STM? If there is, is it substantial to the point where this lens would be unwise to purchase?

The 55-250 STM seems like a very nice addition as I would still be able to use my 18-55 STM, but I am not super excited about changing lenses. However if the 18-135 STM has poorer IQ than the 18-55 STM, I would rather buy the 55-250 STM.

Now the elephant in the room is the Sigma 17-70 "C". On paper it seems awesome but reviews show that its a bit soft wide open at 17mm, and results are best when stopped down. But is this lens worth the price over the other options if I have to shoot at a higher aperture?

This needs to be a sticky:

(Not in this order) IQ, price, weight, focal length, zoom or prime, speed, build quality, Canon or 3rd party, stabalization, suitability for video - all are variable compromises in lenses that have to be researched and considered as to how they relate to your situation. Asking a large variety of people on a website each with different needs, often trying to justify their own purchases will probably not be that productive.