An affordable must have prime lens for any bag.

I tend to agree with you. It has to be handled with care. I have beta-tested Topaz software for a number of years and love what they do. Great company as well. Amazing support from the crew there. I highly recommend their software.

As for this subject, yes, it works pretty well to sharpen it for the weaknesses in the corners but it does look oversharpened and of course, mixed with compression errors. These days, I also don't get all that worked up over corner sharpness like I used to with most UWA lenses. It has never affected any sales for me. Ironically one of my top-selling prints was done with a 5Dmk2 and an EF 20mm F/2.8 lens which I sell on 6-foot canvases. The edges suffer from strong CA and softness, which at the time I never corrected. Nobody has ever complained, including my fantastic print vendor. 
This compared to things shot back in the past is still quite a bit better than some of those budget lenses. Topaz Sharpen just elevates it further and leaves one with several thousand in the bank to go on a nice trip somewhere.

stevvi wrote:

ProDude wrote:

is a shot like that processed in Topaz Sharpen AI. It makes that lens output more like a $2500 prime as it erases any weaknesses in corner sharpness (which that lens tends to have). This way you don't have to ever be concerned about it not being essentially perfect. I don't know if this redo done in Topaz Sharpen AI will translate here with all the annoying compression uploads on this site have to endure, but it's unreal believe me. The increase in detail in the trees to the right of the image is outstanding. Sure resurrects whatever that lens isn't doing.

I find Topaz Sharpen needs to be applied carefully otherwise it causes horrible artefacts in the areas it struggles with (such as the sea here). I find I also feel it tries to oversharpen things at times so needs toning down. That said, it's an mazing piece of software.