Quarkchain is the best ico of may in my opinion. They have a very good team and community. I think they will not have difficulty in entering the exchanges.
It's also high on Ian Balinas list and he probably did a lot of research on them...just wonder do we really need another Blockchain that is scalable? There are plenty of other next gen blockchains and some of them are going on the main net as Rchain after the summer.
If the market is really coming back there will be room for more, if we continue to go sideways then we probably have already to many different blockchains. So I would not jump on that one yet, but maye I am not aware of all key differentiators yet.