20mm and 70mm F4 wide open look pretty sharp to me even at edges/corners, 70mm is slightly sharper. The only issue is that the latest Lr version still has not included this lens' profile. From what I have seen, this lens will meet my expectation that will replace Tamron 28-75 G2 (sold).
The Canon RF 24-105mm F4 L IS USM zooms a bit further than the 24-70mm F2.8, and while it gathers less light, it's a fine choice for photographers who prefer a bit extra zoom power. MSRP $1,299.00 At 24mm with a wide open aperture, the 24-70 f/4L IS bests the 24-105 L IS in sharpness by a modest amount. The 24-105 L delivers a sharper image at 50mm f/4, but at 70mm the 24-70 f/4L is back up to near equality with the 24-105 L. These two lenses perform more similarly at f/5.6 and at f/8 their results are nearly identical.I have the 5D Mk III, 60D, 24-105, 70-200 f4 IS, 50mm f1.8 II, and Sigma 35mm. I use a double strap by Black Rapid to keep the 5D and 24-105 on my right and the 60D on my left with the 70-200. And let me tell you, for the critical shots inside the church I have the 24-105 to my eye about 80% of the time.
. 226 106 484 169 192 386 356 122