I used SunMaster o book an all-inclusive to Turkey in July 2013, their prices were ridiculously cheap but I did encounter a few problems with them.
Firstly they see a child as 17 or under, and give you a quote based on that price, but most airlines and hotels see a child as 12 and under, so your final price jumps up, rather than the original quote.
Secondly their communication is very, very poor. If you are the sort of person to want to speak on the phone to your travel company, do not use Sunmaster, they have about 4 people working in their office, and are all Indians who barely have a grasp of English, and they don't know the difference between Hand Luggage and Hold Luggage. To make an inquiry you have to wait for and hour and a half on a premium rate phone line, or wait 2 days minimum for an email reply.
But then the prices were incredibly cheap, I got a 4* hotel in Turkey in July for £335 per person, flights and transfers included.