Hi @crypto.piotr, thanx for your reply. Actually, the return cover cost of the promotion + give 0-20% extra, so it's worth. But a good point is that this is just one solution and not done by the development (as I think) and the tokens economy seems to be really broken. Well, hope that it will change.
About Q tokens, check this article, I think its one of the worthy tokens.
About @qurator I wrote a few months ago here, while the rules might be a bit changed due to the time.

ritxi