Pixel Peeping alert: those with pixel allergies should not consume this material.
Here's a link to an urban landscape series, shot from a high vantage point and from the same tripod and during the same session on all the above-titled lenses at all main focal lengths and at F4 thru F8. All images are downloadable at 100% size, developed from RAW to 92% JPEG quality. Sharpening was set to 60/0.7/70/20 in LR, which is a bit too much for the prime and not quite enough for the zooms. Camera Standard profile was used. Otherwise there were no alterations and no lens corrections at all.
The results could be pored over for ages but the summary is that you get what you pay for!
There are small bits of some frames where the lowliest zoom seems a tad better, but massively overall it loses to the 24-70 despite that latter lens having a slightly soft left hand side. The 24-70 when shot at F8 and viewed at 50% is close enough to the 55mm in quality as to make it a sane preferred choice for some shooters. However, the 55mm lens is still better, and is faster and can 'do' edge to edge even wide open: it is the only lens of the three that performs to the sensor's abilities and the only one that looks like medium format across the frame - at the cost of some pretty nasty moire in at least one place that is absent from the zoom's version of the same.
Focus was magnified manual for every frame, on the two rectangular windows bang on centre, one dark and one light, set in a grey mansard.
Peep on my friends!