I use all three TSE's, both conventionally and then for seamless pano stitching. By assembling two horizontal frames you end up with a 4x10 aspect ratio that is about 67% wider than the original focal length of the lens, so the 24 is effectively a 16 FoV; the 45 a 30.
Here is a shot of a graffiti wall done with the 24. I have the camera about 2 meters from the close wall. Note the edge fall-off too -- this may affect your decision. Canon only recommends using 8mm of shift in horizontal mode with the 24, but here I used all 11mm so got the last 3mm of fall-off on both sides of the image. I personally do not mind the effect, but you may:
Here is a similar stitch done with the 45. In this one I am around 4 meters from the kiln and it is about 5 meters tall to put things in perspective:
Note that these frames were all assembled directly in CS. It takes me less than 6 seconds using counter-shift on the camera to capture both frames required for these perfect stitches
Hope this helps,