Re: Roland or Yamaha?
I've owned both Roland and Yamaha, and personally Roland is the brand I prefer as the sounds just seem a little more 'real' to me. The mesh pads was another important factor for me when deciding which brand to upgrade to. But it really is down to personal preference and I think most people would be happy with either!
Couldn't disagree more with those saying there's no sensitivity or ability to play ghost notes and accents - I can get a great range of sounds from my Roland (just as I could from my Yamaha) and so can many other players.