I have registered in neobux 3 times, first time for free, other 2 times with invested money. Please be advised that people in neobux think that they will get exponential growth and earnings which is not true, the average clicks of the referrals after one month drop below your profit zone meaning you will not be able to renew them and will be at loss. You can try this for yourself by investing $5 and renting referrals for one month, see if you are at loss after 1 month.
If by some chance you are in profit after 2 months, then invest more, but i highly doubt it because the system is made that it eats your earnings away and you barely keep your referrals alive.
I advise you to go at neobux forum and check the stats of normal users, you will see people with golden with 1 000 referrals that have -$0.50 to +$0.50 net profit per day, the cost of the referrals is made in a way so that you do not earn much or be at loss.
To get real profit you need to invest thousands of dollars which in my opinion is very risky because to get back your investment you will need at least an year or two in which time neobux may crash.
The other thing is that if you cannot earn money while being standard member why should anyone think that they will profit if they start investing? If the system is made that you cannot make money without investing, why get the idea that you will earn more if you invest? Even if you get the illusion that you are in profit with 10-20 referrals, with each 100 referrals the average clicks drop, and you start being at loss, you get another 100 referrals to boost your earnings, but the average drops even more to compensate, its like somehow the system knows the number of your referrals and gives you that amount of clicks? If the admin cuts the cost of referrals by half, then people may start to profit, but now they barely have money to renew their referrals and keep investing.
Check the forum and the stats of the users, read their stories, even search online at google for other people stories about neobux because bad stories get banned on neobux and then decide.
For the other PTCs i advise you to do the same things, search online for reviews of the said PTC, check if the PTC have been online for more than 2-3 years and then try it out with small investment $5-$10, to try if the referrals are good after 1-2 months and then invest more if you are happy and in profit.
I am also searching for PTC to invest in and am looking for an alternative to neobux that have good average to the clicks of the referrals, meaning the PTC is profitable and doesn't eat your investments.
This is why i found this site to check some reviews and find better PTCs then neobux.