I git the powershot elph 520 hs "12x optical zoom." It is solidly mediocre-- blurrier photos than I've ever had with an extensible-lens P&S. The 12x optical zoom is still crap, even when you steady the camera on an unmoving object with a timer. Check the reviews for your model, see if they have any commonality with the 520.
I wouldn't get any of those 4 cameras. Here I am assuming you are more worried about weight than price to pick those four models? If its price, then take those 4 models you chose, and get the previous model number or two previous model numbers as they are no different and can be had for half the price. IMO They are all mediocre/junk at best unless you want to primarily use such a camera to clip onto your rack only. In that case they are great for clipping on ones rack as cameras much larger than this get a bit cumbersome.
Someone upthread voiced opinion for Fuji X10/CanonG10 and their ilk. These cams with the same sensor are vastly superior to the models you have chosen, but do weigh more and likewise cost more. They are still clipable to ones climbing rack, but IMO anything larger than this and they tend to swing around too much.
There are of course large sensor cams, but they are not really good for clipping to your rack and once again cost more and weigh more, but you do get vastly superior photos, though if you are like my father, can still take horrid pictures with a great camera. He makes up for by taking thousands of them and some of them actually turn out on accident. =)
Ok, enough denigration of those small sensor cams. One can still take good pictures with them if you learn to use the exposure compensation dials like mad. The biggest problem with all those small cams is their white balance is horrid to mediocre bad generally. If you practice, these cameras will suffice, producing images good enough to print large to very large if stitched.
PS. For very steep rock climbing, clipped to my rack, I still use a 5mp cam... Good enough is good enough for screen savers. Only very good landscapes do I print and all of those except 2 have been from "real" cameras. The other 2 were both multi stiched using the aforementioned old camera.