I bought the One Touch can opener, because I thought it would be easy to use with one hand.  My neighbor had warned me against buying it, but I got a good deal on it and tried it anyway.  It was easy to use with one hand, but it never opens a can on the first try.  I have to restart it several times, before it opens the lid enough for me to twist off the lid.  It usally leaves a little of the lid still stuck to the can, so I have to twist it off.  It is supposed to break the seal between the lid and the can, but all it usually does is make a mess.  I open very few cans, so I still use it...