Daytona 116509 WG Z series - worth buying?

[soros05]

I have decided to buy a WG Daytona and are given 3 choices in a non-AD watch shop in Tokyo Japan:

1. new M series with new bracelet - JPY1.9M or Singapore dollar 30k or USD21.5k
2. new V series with old style bracelet - JPY1.8M or Singapore dollar 28k or USD20.5k
3. used Z series - JPY1.6M or Singapore dollar or SGD 25k or USD18k (can see a slight scratch of the ring.)

Which should I choose? Need advice urgently as leaving Japan soon.

Thanks