It took a little bit of digging, but I found this (the uncorrected 24-240) https://keyassets.timeincuk.net/ins...1/Distortion-24mm-Uncorrected-Raw-533x400.jpgBest digital cameras and lens reviews. If you are looking for the information about digital cameras and lenses you are in a right place. We have many professional tests of digital photography equipment.www.lenstip.com
It looks worse, of course, but it's projecting a much wider image. So one should look at the central APS-C sized part of it. Just eyeballing the innermost 1/1.6 of it at 24mm it appears to be comparable to the Tamron--I suppose one could take that image and crop it down, then make it the same size as the other one...but I see little point. Of course if you compare it CORRECTED to the Tammy uncorrected, it's going to kick the Tamron's ass.
The designers at Tamron clearly expected it to be zoomed in a lot more than zoomed out; the grid looks pretty darned good at 400 mm.
I don't know about sharpness, etc, but from a sheer distortion standpoint I would prefer the Tammy--after all it's a 22x zoom, vs the 24-240.