'Better' depends on how/what you want. The RS antenna does well on 2 meters and that general area. It will do less 'well' the further you get from that general area. It just happens to be resonant on 2 meters. I've never owned an 'ST2' so can't make a comparison. Going only by what I've heard and the general construction of the thing, I think it would probably do 'better' than the Radio Shack antenna, maybe.
Not much help, huh?
- 'Doc