Cheapest one I can find is £139.98 via abe books http://www.abebooks.co.uk/servlet/SearchResults?sts=t&an=shee+twohig&y=0&x=0&sortby=3
The most expensive is £642.14 via amazon
http://www.amazon.co.uk/exec/obidos/tg/detail/offer-listing/-/0198131933/all/sr=8-1/qid=1154837073/ref=sr_1_1/202-8318685-0031868?%5Fencoding=UTF8&s=gateway

for £642.14 you could buy a shedload of easy jet tickets, visit many of the sites and make your own mind up.