Don't listen to the haters. (no offense Adam, just hecklin' ya)
Yes the mk3 is heavy but my take on it is this (I still consider myself a novice so take this is FWIW)
I see it as being 75% driver, 15% tires, and 10% vehicle. The mk3 is capable and yes it's outclassed but I think it can be competitive (at least that's my goal to prove) At my last event I placed 2/6 in my class. I was a second out of first to someone on R-compounds and beat two others with dedicated tires by a second. All of these drivers have been competing much longer than me and my 5 y/o dunlop SP6000's. I'll let yall know how it goes when I make the switch to good tires next season.