Shell Rotella Diesel Additive

Along with the Rotella synthetic 5W-30, Walmart now has a Shell diesel fuel additive. It's dollars more than the Power Service brand. Also says to use it every 10,000 miles in the summer but every tank in the winter. Anyone try it?

I have been using it for about 6 mounths. It works about the same as power service, i didn't notice any differance. i got mine at sams club $33 for a case of four 96oz jugs with an $8 rebate(works out to about 2 bucks a quart). Good deal if you get it for less then power service but i would not pay more, i don't see any advantage.

http://www.buyduralt.com/ is another one.I'm using it now and you will see a slight mpg increase.Check it out.