For piece of mind without the hole in your pocket, try AutoAid only £32:
http://www.autoaidbreakdown.co.uk/
Covers the person not the car, great if you have multiple vehicles, free cover for spouse/partner, onward transportation included, home breakdown recovery (limited to £45 max), and did I mention it's only £32. All you got to do is pay up front and claim back later, anyway as you said you don't expect to break down in your Lex do you? I have a policy, flat battery in my old Focus after a 3 week holiday, cost me £45 to have someone come jump it, that itself paid for my whole year's policy!
For other cheap and more conventional breakdown cover, try these options!
http://www.moneysavingexpert.com/cgi-bin/v...094823518,14076,
Otherwise Gold members have discount with a major recovery service, check it out.