Seems to be a common problem... I had mine replaced after it went out the first time. I had no pressure and I was 80 miles from home
Since then clutch has been good but lately I have been noticing the pressure is slowely going away again. Somedays its good normal pressure and some days 75-80% and about an inch less travel.
Soon I will be replacing the lines with better quality and Im thinking about an aftermatker raplacement booster. hopefuly that will solve the problem or stop it from happening again.