NeoBux is working fine, I'm using that site currently. Though they are not the king of PTC anymore since their removal of PayPal. Most PTC sites have more payment options currently (NeoBux to date has no option to handle transactions with cryprocurrency, for instance), and the rented referrals on NeoBux seems to be less consistent than the ones on Twickerz, YouGetProfit, Cliquebook or Cliquesteria.
PTC sites are very low in how much money you can earn. For instance, you'll need around 125 active direct referrals on Twickerz in order to earn $1 per day in referral commissions. This is crazy high time investment for a minimal reward. Compare this to, say, some affiliate marketing discussed here and you'll easily see why the community isn't too fond of discussing PTC sites.
This being said though, I think that PTC sites have a place. They're a source to get traffic and learn about banners, text ads etc. (I know this is also controversial to some, but you do get real users clicking ads if you buy ad credits there, and some have built in traffic exchanges and other features). They're also a working introduction to breaking the psychological barrier to making your first money online, as accounts are free. Even though you earn like $0.001 for each ad clicked, people still get to do something resulting in a reward. This first step to making money can have value in being a stepping stone, and I think this is understated.