When I first got the Zed the TC was off due to a fault and I found the car very informative when driving. If it was going to go, I knew about it, was prepared for it and it was very controlled.
At present I have it turned on as the roads are slippery and unpredictable with the volume of leaves that have fallen recently. I do find it intrusive though - as others have said - and by cutting all power, would be dangerous in some situations. It is a reassuring back up though and certainly worth while as you are getting to know RWD characteristics.
Would absolutely recommend an airfield or similar day to turn it off and really test your car though...I will do one in the Zed once the new year arrives to send my rear tyres over the wear indicators in style!