There are many good thing to say about this product. With automation and AI many jobs are belong lost and people will have to find some little gigs and micro-tasks like this a a great place to start. aQuest can be a great place for people in developing countries and young students/school kids from developing countries.
One common problem among this type of websites/services is the trust element not begin very high. With blockchain we can build a trustless system.
Only having ERC-20 tokens is bit of a co i my option. They could have picked EOS or TRON.