I've been using LA/Fritz salt for the last 2 years without any issues. Always mixes up consistently, fast, and clear.
I try to buy the buckets/box when they are on sale for $50 or so.
At some point, Amazon had a crazy cheap sale on IO, so I bought one small bag to try out. Figured I could use it in my QT tank or something.... I mixed up that one bag and I did not like how it dirtied up my mixing container and left a brown film on everything. I'm sure it's harmless, but I'd rather not deal with that if I don't have too. I'd rather pay a few extra bucks and stick with the LA/Fritz salt that doesn't have any of those issues.