I left recently, I paid the bond, for a couple of reasons;
a. Although I took home legal advice and was told there would be no difficulty at all challenging it at home - the legal type did say 'but you have to get home first' - kind of a chicken and egg situation.
b. The legal type then said it would be better to clear it all up prior to leaving the UAE, which means local lawyer - v expensive and frankly, you can't be sure you'd ever get it tidied up to your satisfaction.
c. You can offset your provident fund balance against your liabilities so, although you won't walk with the cash you can soften the blow.
d. I jumped a bond once before and the employer made sure my next employer knew about it, as it happens I had preempted the situation by advising them of the circumstances so it was a bit of a damp squib - but could have been untidy.
e. You jump bond in the UAE and ever end up passing back through here standby for some drama - you can be sure they'll get you somehow.
One thing that did become apparent when I spoke to the lawyer was that in order to make your claim against the compnay completely watertight you should send a written letter to them, in a timely manner, after every perceived change to your terms and conditions registering your displeasure/objection to the change - if you do nothing it could be perceived as tacit approval.
If it's any consolation, paying to leave was the best thing I've ever done - now feel about 15 years younger and I have absolutley no regrets about going.
PM me if you have any other Q's