Cho is the man! He was supposed to simply guide Ed for 5 days and then he just decides that he's going to come along too! I wonder if he was just like "Welp, I think Im'a go with you to the mouth. I don't have much else going on sooo.." These guys are living a dream of mine. They are on a real adventure!
Now, this adventure doesn't match the like of Captain Scott's polar expeditions, which conducted rigorous scientific studies, but this is still pretty cool. Traveling is harder when science is involved, and the nature of the studies lead to more land impact, so I'm not too discouraged. Still, imagine what they could provide as far as flora and fauna collections.
As for being the first to do something like this, it is true that he probably isn't the FIRST person to any of the places he is visiting. However, recording his journey is a first, and I hope he is documenting more than is apparent from the blog. That is where knowledge is gained and passed on to the masses (scientists).