One of several great things about 100% PoW is that it isn't ideal as a scam/ponzi/P&D coin because distribution is open to anyone doing the work, is expensive and any weak PoW currencies who don't capture the interest of the public with true innovation quickly get attacked because they don't have the mining hashrate to sustain against an aggressor.

You can easily spot a scammy PoW coin by it having a extremely sharp rather than gradual distribution curve - I.E... Quark.