Actually interactive fitting only VMD is providing and that is also very limited. VMD chops off your actual EM map according to the provided pdb model instead of fitting it into the density.
So, as I want to fit multiple structures in the map, I can not do it. I was trying to fit my multi-chain PDB in the same map but it failed.
Chimera do not provide interactive fitting and it fits the protein poorly in the map. Therefore, it is hard to get a proper knowledge of the conformation of any of these tools.
Rest tools are more programming centric, making them hard to be used by biologists having limited programming skills like me.