I changed the wiper only on both the passenger and the driver sides. It was a pain in the neck because I had to buy the blades and remove the wiper (not an easy task) then put the wiper on the original blades. The wiper itself has three parts. The rubber piece and two small metal strips.
The refills that match the factories wipers are Michelin's and can be found at Wal-Mart for like $6.99 or something like that. I think they were $9.99 at Target. I wasn't going to get rid of the blade with the spoiler built onto it, it works too well. Good luck!