Group Deals

I've been seeing lots of Groupon deals for luxury villas in Bali and Krabi. Some of them look really tempting as they are sold at more than 50% discount from the retail price. Some of these luxurious villas include rain showers, huge baths and ipod dock for you to listen to your favourite tunes! Isn't that great? I'm really tempted but am worried I may not get the real deal if I purchase through a group deals site. Do any of you have experience buying holiday packages