I already have a DVC30 which I'm very happy with. Most of my filming is done in very low light and the DVC30 performs well. Now I'm looking for a second machine. Apart from another DVC30 I am considering the DVC60, mainly as it's shoulder-mounted and easier to avoid shake issues.

Am I right in thinking that the DVC60 will match the 30's low light performance?? thanks

Yes, the 60 is same cam inside as the DVC 30. However, if you do shoot a lot in low light, why not look at a Sony VX2100 which is rated at 1 lux? Cost is so very close on them both, that's what I would do. Matching output should not be much of a problem, either.