its wierd, on my MK2 I have an abf, poly wishbone bushes, solid front, bonded rubber box and 16v/g60 rear mounts. all fine, no punch in the kidneys when starting, no real vibration problems of any kind to report. My mate has exactly the same setup in his MK2 and vibrations were much worse than mine.
Only difference is I have a good quality 40mm lowering kit, he had coilovers. maybe the condition of the front engine/radiator carrier bushes makes a difference?