Recommend that you drive as many as you can they all have their own characters.
I note no one's mentioned the rev-hang which stopped me buying one of the very last Series 4.
The problem with mentioning 'rev hang' is that some do, some don't regardless of model / spec / age / of Roadsters, I've even witnessed it on some 4/4's and +4's. Then add to that the willingness of some drivers to adjust their driving style and it can mostly be 'dialled out'