I've used both Stanadyne and XPD since the change in fuel. Stanadyne until the test came out showing the excellent results of XPD. I purchased 3 gal. of XPD and have used most of 2 gal. The XPD caused more noise than Stanadyne and also a slight loss of MPG. No improvement in response. Both are spendy. I tried and have switched to 2 cy oil in my 03, less noise, smoother and more response. At the suggested ratio of 200:1and at $11 a gal at Walmart, a 25 gal fill with 16 oz., cost $1.37 of 2 cy oil. Stanadyne was about $2.50-$3 a fill and XPD about the same or more at the winter ratio, about the same as 2 cy at the summer blend. Now my 2 cy result were with a ratio of 128:1 and some XPD remaining in the tank, only 2 tanks so far, so I do not know what noise, smoothness, or response will be at the reduced 200:1 ratio, next tank. Here's a story that made me nervous of XPD. One of the gal jugs cracked and began seeping, so I poured the remaining XPD onto an empty Howes fuel treatment jug, about a qt. The next day I noticed a puddle of fluid around the Howes jug. Thinking I had spilt some down the side when filling the jug I picked up the jug and it went to mush in my hands. The XPD had destroyed the container in one day, wow, yes it's a solvent. It was too late for rubber gloves as now my hand were covered. I washed and washed and washed, rubbered up, safety glasses and poured the XPD into glass, called for an MSDS that came with in minutes, very good service. Reading the MSDS, yup this stuff scares the crap out of me, got some killer stuff I don't want on me. But all these chemicals we use have stuff I don't want on me or in me(through the skin) including 2 cy oil, reg oil, grease, none of it. This stuff ain't the same lube's and oil's I grew up with and used to have up to my elbows, they're now all real chemicals and dangerous. Rubber gloves and safety glasses are my rule when servicing my truck. I don't even let diesel fuel get on my hands, I use paper towels at the pump and I always wash after fueling.