Hoyhoy.
IMO a lot a depends on whether your going for a DSG or manual (I don't like the DSG) my daughter has had several Golfs, @ present has a MK6 R with a manual which is a ripper, another one she had was a MK7 with the DSG this didn't stay long in her hands from new . Another one she had was a MK5 GTD but it was modified too much & that one left her hands also soon after. I've had a drive in all her Golfs & the best one she had was a new MK5 TDI manual, (she is still sorry that she sold that one). it's just the low down torque for every day driving, I loved that one.
She's had more cars than I've had trips to the toilet.
P.S. The MK6 is the best looking of all Golfs because of the tail lights, they don't look like a maccano set or a jigsaw puzzle piece pushed in.
All the best in your choosing & this is just my opinion.