I am going back to Injex, from Phillips. I used to use it and had no problems. It burns clean and is readily available at most Phillips stations. The snow-mobile guys really like this stuff, its TCW-3 also. I have been using Water Pumper for about a year without any issues, I just think that there isnt any added benefit using it even though its a partial synthetic where the Injex is all mineral base. I run my ratio at 28:1 without any spooge or plug fouling.
I dont know about the Wal Mart stuff, personally I would run the Injex over that stuff any day. Also the Injex is less than $10 a gallon if cost is also a issue, for me its not that big a deal, I just like the Injex.