My Mantis is 2004, and last few years has been a nightmare--and continues for 2015. I never really bought the "new gas" scenario, but after trying this last weekend and having it barely run--I did the new gas Monday AM (used regular, though). Got it started and it ran like a dynamo for about 20 min--so now I am a believer in new gas! Shut it off for few minutes of raking, and then could not get it started. Rest of week same scenario, mess with Carb, changed filter, checked spark arrest screen, checked plug, used carb cleaner on "L" jet(rebuilt carb last year)--run's fine for 5-10 min--and then quits. Talked to Mantis twice this week--little help, except comments on bad gas these day. Am ready to burn it in town square in Cary, NC.