Read their whitepaper!
I don't think that a project's whitepaper is enough to determine its legitimacy. There are a lot of factors we need to consider such as the team's track record, opinion of others in the community. Luckily Menlo One will be launching its decentralized ICO marketplace soon. We won't have to spend so much time checking every ICO and we'd get to just pick which we think is the best investment...