Favorite brand of packing cubes?

[squirk]

I think I am missing something on travel cubes. For years, my family has been using those large Ziploc "big bags" to organize our travel clothes. The bags are large, cheap (~ $2-$3 per bag), sturdy and transparent. By rolling the bags with our clothes inside, we prevent wrinkles and compress everything by removing all the air.

What can storage cubes do for me that the Ziplocs can't? I really would like to know.