I managed to sell mine (to a trader, so cheap!) and cleared my finance and still had about £700 cash back.
I only put in the minimum deposit too.
Its all about timing with these things. If you just wake up one morning and decide to get rid, you're going to lose money!! If you wait, judge the market, keep an eye on your finance owed, there is no reason to take the massive hits.
And if the worse comes to the worse and the market drops onto its ass, then you just keep it full term and hand it back.