I have 2 v-spec's and a VZ-r. The second V-spec I bought with 3 gallons through it. It runs as good as my new one. I have not had any running issues with them. I disassemble them about every gallon or so clean them and replace all seals. I don't blow the grit out of the front bearing with an air hose. I rinse it real good with alcohol and then lightly air dry it. If you don't blow dirt into your front bearings they will last a lot longer. I run against p5's and WS7's. The WS7 seems quicker than my V-spec. The fuel I use is 20%. Most of the guy's I run against are using 30%. The rb guy's are tunning a lot more than I do.