I prefer the dr100's for gaming.
The Dr150's have a fuller sound to them, and tend to push every detail of the game into your ears, because of this they seem to amplify the ambient sounds more than the 100's, which i find can hinder the positioning of footsteps, and gunshot.
Because the 100's lack some bass and are more subtle on your ears the positioning is excellent.
Music is another matter, if i plug the 100's and 150's into my headphone amp at the same time, you can hear the difference even before you put them on your head. The fuller more detailed sound from the 150's is a step above the 100's which to me sound a little flat for music, compared to the 150's.
Apart from on the odd few songs where the 150's's tend to trip themselves up by pushing to much detail and everything just becomes a mess of music.
You will be more than happy with either of the Goldrings, i just find it better to have one for music and one for games because of the difference in the sound. Especially for the little monies they cost.