Simple low light test of Sony PMW-100 and JVC GY-HM600, which are about the same in price. Shot in room with very faint lighting, a lone 25W halogen lamp. Both camcorders set to 1.8, 1/33, variable gain. Did it quick and hand held, sorry for shaky footage but maybe the comparison can be helpful for someone.
I think the JVC is the most price worthy camera of the two.