What can I say SAB Goblins are the sexiest Rc Helis on the market they sound great
And fly awesome people say they are heavy
It's never bothered me try fly a logo 800 on 14s now that's a heavy model

 

I think a bit of weight is important for an aggressive flight style and a bit of wind. I believe most 700 goblins are about 5.7kg. Maybe get some samples on some scales?

My model is 5.6kg and I think it's just right.

 

It all depends on what motor & ESC / packs you run in it take all that out and I don't think there would be much difference
In weigh

 

I also think where goblins might be heavier is the beefy head design. Its pretty solid and wide! Im going to weigh my gobby.... give an official no battery weight...

 

Yes the KSE 3 blade head and tail will add more weight but on the flip side you can run
16deg pitch at 1800 with no problems

 

I can only speak for the 570, as it was the only Goblin I have owned. But it did not seem heavy to me...even on 12s. I never did weigh it when I had it, but it was no heavier than my old T-Rex 550E.