We have marbleworks but my almost 8 year old wants to "trade" it in for the one in your third link because of the looptaloop. The marbleworks one is great however and all three boys play with it all the time. Easy to put together and stays together well.
"Someday, I am going to go to bed without toys on the floor and sippys in my sink. Things will stay where I put them and I can have nice, fragile items on display. But when I do, I will look around with a wistfullness in my heart and miss the days where vibrant imaginations ran wild and there was evidence of life happening around me all the time!"