I buy the Wal-Mart brand - I'm not sure what that is. I bought it a ton of it when it was on sale. I remember you used to be able to buy it for 99cents and now it's close to $2! I have bought Rain-X before but that is so expensive.
I use whatever happens to be cheapest at the time. I have a problem with my tank though. My hose came off that runs to my back wiper on my truck so I can't fill the reserve past a certain point or it spills out the back end.