I'm impressed with the poly bushes pureley from a quality design easy to install, last for ever point of view over the crap, sub-standard, wear out too soon, have to replace the whole arm items fitted as standard.
I must say I've never had any rattles noises from my suspension even when the old bushes were well knakered - but then I don't really get to drive on particularly bad roads.
Can't say I noticed a great difference in ride/handling with average speed motoring compared with the old bushes, seems slightly stiffer at the back end perhaps. Maybe hard cornering on a track might reveal a significant difference.
Just for info my Alfa specialist recomends replacing the whole arm with the stronger 3 litre arms as these have a swivel bearing rose joint at both ends of the arm. The 2litre only has this at the outer wheel end of the arms the inner bushes being the weak fixed items (design fault). Apparently Alfa have now revised this & fit the same 3litre arms to the latest 2litre models