I realize 20 lb paper is cheaper but it sometimes sticks together and pulls through 2 sheets at once printing part of the page on each piece of paper. 26 lb paper is hard to find in Staples store and never has a discount on it.
Just a quick visit to buy printer paper nothing special (it seems that everyone wants a review these days regardless of the service or size of a purchase - if you sneeze it has to be reviewed!). I can only say that I can't remember ever having a bad experience at Staples.