Wal Mart's Super Tech DEF?

I use the Super Tech DEF. You do have to be careful though, there is a Walmart near me and most of the jugs they have on the shelf usually are just water. You can tell when someone has refilled with water and returned it. Look for crystals around the cap, and ALWAYS take the cap off and check the seal. And use your finger to check the edges of the seal, most of the time the low lifes have tried to re-seal but you can tell its not a good seal.
I have warned the staff at the store of what I have seen, but they didn't seem to interested in it.
The Walmart on the other side of town doesn't seem to have the same low lifes shopping there!