I see your point. I guess I don't get bored with things when I like then, just the chance to have an even newer version for a fairly small financial penalty appeals 
There is nothing wrong with having the same car as your next car if you get me. I drive a CC at the minute(or at least I would if the repairers were finished with it) and I would have no problem ordering a new one if they were not bringing out a completely new one in the near future. Hell I would even order it in oryx white again.
For the £40/month do you get any extras over what you have at the minute? Also when does your warranty run out because that is something else to think about.
As already said 10% doesn't seem that great, I got offered over 18% off an R with most options ticked. The worst thing you could do is rush into anything on the spur of the moment.