There's nothing inherently wrong with doing it in both places.  I can see if you are editing in Photoshop where you'd want to just complete the job there, but keep this in mind.  Qimage has Deep Focus Sharpening which is leaps and bounds ahead of unsharp mask in that it can sharpen without artifacts like halo artifacts.  My advice would be to sharpen in Photoshop if you are doing creative sharpening like sharpening only some layers or subjects but if you are adding sharpness to the whole image, just don't do any sharpening in Photoshop and do it all in Qimage with Deep Focus Sharpening.

Regards,
Mike

Good question.  The strength slider still controls the amount of sharpening as you slide it from off to med to high when you use the static option.  As you go higher, with both modes (smart and static), both the radius and the strength are adjusted higher as you move the slider.  The difference when using "Smart" is that it will further adjust the radius and strength on a per-image and per-print basis based on the resolution of the image itself, how big you are printing, the resolution of the printer (driver), etc..  Therefore the "Smart" option is able to keep the same amount of visual sharpness whether you print a 4x6 or a 30x20 inch print, and whether your driver is running at 600 PPI or 1440 PPI.

Consider that there are two steps to sharpening.  First you should double click on the photo to open it in the editor and use DFS on the image itself (if needed): get it as sharp as you want it on screen when viewed at 100% (no zoom).  That corrects for any softness in the actual image.  Once you get the image on screen to the desired sharpness, print it and see how sharp the print looks.  Match the sharpness of the print to what you see on the monitor by using smart sharpen and setting the sharpening slider.  Then you can be sure that:

(1) The image is at the proper sharpness and
(2) The sharpness of your prints will always match that of the monitor, regardless of print size

The smart sharpening is typically a "set it and forget it" option because once you find the level of sharpness needed for your printer (and paper) to match the monitor, it'll hold that level of sharpness and you've got a match between monitor and print sharpness.  Final note, QU saves those settings when you save printer setups so you may need a little more sharpness for matte papers for example.  If you save a printer setup for matte paper, that smart sharpening slider is saved with the setup: when you load the matte paper printer setup, the sharpness for that paper will be recalled and when you load a saved glossy setup that may have required less sharpening, the lower sharpening settings will be loaded when you load that glossy paper printer setup.  And so on.

Honestly, I leave mine on the default as I find it produces razor sharp prints with no halo artifacts, but all printers are different and some people may prefer a different look, hence the adjustment slider.  The ability to save/load printer setups also means you could save multiple setups for different looks.  For example, you could save one called "Canon Pro-1000 Semi Gloss Landscapes" and another called "Canon Pro-1000 Semi Gloss Portraits": same paper but you could adjust the sharpness lower for portraits if you want them a little softer so they don't show all pores and skin blemishes on portraits of people.  Of course, another way to do the same thing would be to not sharpen the image itself (step 1 above) as much, or even soften it before you print it, and just use the same printer setup.  But the choice is there.

Just some tips.  Hope this helps.

Regards,
Mike

If you sharpen parts of the image in PS and you still need some overall sharpening applied to the whole image, it is best to do that in QU.  The more sharpening you can do in QU the better since QU has DFS which is halo-free and better than the sharpening methods offered in PS.

Regards,
Mike