I was reading about this project few days ago but due to confusions like mining process and also the tokens involved in the mass network i just skipped it because there were apparently 2 tokens and usually i do not like projects with multiple tokens its just makes things complicated so there should be one coin so that we could be clear about price and utilities.
There was a token esh who at first ran on the development of esh but later they came up with a new token like multiple. In addition, the price of esh increased a lot in the beginning but later it dropped a lot due to which many holders lost money. However I have less idea about the tokens in the list of op but I can say do good research then invest.
These are golden words "Do proper research before investing in any coin". As far as my knowledge is concerned about MASS, its doing good both in term of mining and at exchanges. Important thing is they are building a community to backup the eco-system.