You would be much better buying a pre reg car,if you hang on until about 2 months after the new reg comes out and the new one is due you could get thousands off.
I always do that and get a brand new no mileage car for a massive saving on new,I got 4k off my last one.
The dealers need to get rid of any cars they have left from the previous reg before the new one comes in and lets face it because a new reg comes out every 6 months now,there are lots of bargains to be had...good luck and still haggle for a while about the price,they want rid, and your in the driving seat (excuse the pun) lol.