Costco clothes are of high quality and good prices. Their only downside is they have little style variation - they basically have hundreds and hundreds of totally identical sets of clothes. So chances are if you know someone else who shops at costco you can be caught wearing the same clothes fairly often.
To be nobody but yourself - in a world which is doing its best, night and day, to make you everybody else - means to fight the hardest battle which any human being can fight; and never stop fighting. -- E. E. Cummings