[Seraphin238]

A quick note on the engines you mentioned. The 170bhp won't give you a much better performance over the 140bhp, it will only reach a higher maximum speed, which doesn't really matter on UK motorways (unless you are planning to spend your vacations on German motorways.
The 200bhp has a superior performance (e.g. better acceleration etc.) compared to the 140 and 170, as it is a turbo.

Good luck!