All of them are scams but you can still make money if you join and withdraw at the right time.If you are too greedy you will loose money every time.
If something is to good to be true, then it's not. I suggest do an extensive background checks on any of these so called websites with BBB, etc to help weed out the scams.
If you have to ask if it is a scam, it probably is. If they are disclosing high risks to go with the yield, then there might be something there. There is no such thing as a low risk high yield investment, if they tell you different, run, dont walk, away.
From my experience,100% of this site is scam. They cannot sustain the huge payout such as 10% interest per day.
Most HYIP operations (at least the ones that I had experience with several years ago) are technically not scams but are certainly Ponzi schemes. In a nutshell, this means that older investors are paid with the money from newer investors. Very little if any outside revenue is generated. It is possible to make money with these programs if you know how to play the game and get into a relatively reliable program in its early stages. A good HYIP player must have the discipline to avoid excessive greed and prudently withdraw his/her profits before the program inevitably crashes (money to pay new investors runs out).