I have 3" front and 4" rear all spring drop on my 66. I can't give an opinion on the difference between stock and dropped, due to the fact that the suspension was already dropped by the previous owner.
As far as the ride quality, I would say it is very good. It's much better than the heated stock coils that the prvious owner had. Handling is great. I drive down the highway at 75 or 80 with one hand on the wheel and one out the window. It takes corners well, blah blah blah.
I did not use any shock relocation mounts, but I did get an adjustable panhard bar from ECE. hope this helps...
B