Opinions on coilovers and solid top mounts

To all you chaps out there who have fitted either coilovers and/or solid top mounts, what are your opinions on how they affect the dynamics of the car?

I have recently re-fitted my standard cup springs as was not happy with the handling on lowered H+R springs as I seem to have no steering feel and the playfulness of the car was lost (i.e. more understeer).

Have coilovers or solid top mounts improve steering feel for you and is there a marked difference in handling?

Any advise would be appreciated.