The 70-200mm f4 has internal focusing and more elements the quality of glass given it's L glass tag means it should have far superior glass in it. Internal focusing in nice especially if you want to shoot with a circular polarizer, but it nicer all around. Metal construction over plastic and I believe weather resistant. It won't be super strong in low light but will be better than the Canon 70-300mm compared.
Would I want to lug it around traveling, not unless it was a f2.8 70-200mm, then hands down it would be my choice. But 70-200mm f4 is a better lens than the Canon 70-300mm listed and can be hand new for $675 @ Adorama the 70-300mm is $550 @ Adorama which is a reputable vendor.
The lens you listed is not a bad lens, it's a good travel lens that will produce very nice photos. More often than not equipment is not the limiting factor. Too often people say wow great photo what camera or lens do you have? Must be the equipment right?