Well gmax with one hand me down 070 it possibly is and like me you wouldn't have years and years of experience on them ........... now the days of doing a full days work with them have long gone so it's mainly to have one for the sake of having one without paying an arm or leg for some overpriced worn out thing off ebay and unless your going to keep another 50 years you can get some fun out of it.
Besides mine ain't 105cc but have been upgraded to 090's at 137cc
But you don't really "have one"- you have a copy of a design that was stolen and built with probably inferior materials and labor- that's like saying you have a Picasso or Monetw when you have a copy