I have been using Shamwow as an paper towel alternative in kitchen for more than 6 months. I started with a bunch from Costco for around $30.
As per their advertisement, the Shamwow actually absorb more water than other towels do. But it doesnt long. If you try to use it repeatedly for a week, the capactiy really goes down and it becomes an ordinary towel. But i found one difference between this and also other normal cloth towels. Since the shamwow is made up of material with tiny pores the food particles doesnt get inside and so if wont start to give bad smell as other cloth towels.
Shamwow doesnt really lasts longer, a towel can last just two to three weeks with repeated use.