I like MASS because of some obvious reasons that it only requires HDD to start mining process. Not much infrastructure is required to start mining the MASS. I dont know much about HEX but MASS was profitable in its early days.
Thats why MASS so so hit in its initial days among the mining community. Those who mined this coin before its enlistment on exchange earned huge profits. You just need to be smart and on time to get the profit from this coin.