Sorry, I'm afraid I'm only going to have bad news.
First, once you calculate for crop factor, all of the cameras you listed are over 200mm. (Although, without the crop factor, they are all under 200mm.)
Second, none of them will do well in a low-light concert situation because the lenses don't let much light get to the image sensor, and the image sensor is really small so it doesn't have a lot of area to absorb that light.
Third, with a 200mm (Full Frame equivalent) lens, in order to get an average height 6-foot tall person to fill the frame from top to bottom, you can only be around 50 feet away. Assuming the person is standing halfway back on a 10 foot stage (so 5 feet back), and there's a 5 foot security barrier in front of the stage, and assuming 2 feet per row, you have to be in row 20. The farther back you are from that, the "smaller" the person will look.
Having said all of that, if I were forced to choose one of the cameras you listed, I would go with the HX20V because the lens is a bit brighter than the lens on the WX300, and the form-factor of the HX200V could be flagged by Security as a "professional" camera. (Or, looking at it the other way, the HX20V looks more like a point-and-shoot.)
Sorry - Mark
P.S. If you're interested, I posted some basic concert photography guidelines