If you are time poor Andy, OSC is the way to go.
For the money, Poita's QHY8 on Ice Trade is an absolute bargain.
6MP, DSLR sized chip (perfect on your ED120), COOLED CCD and as I have personally used this camera (Peter loaned it to me), quite easy to use.
Go for it, it wont last long, or might already be gone....
Otherwise, you could try the last 314E mono that is available at Andrews (I bought it as they thought it was colour
) as it is a very nice mono camera with almost ZERO noise and then later, buy some Ha or OIII, SII filters etc and go nuts from Suburbia. Mono Ha shots are some of the best shots going for night skies that have lots of light pollution.
With the ED120, you wont have any issues with lining up the newt diffraction spikes like I would have if I imaged over a number of nights.
The 314E is only $899 and they have free freight on at the moment. WELL worth it as I personally know how good these cameras are as I bought the 314L+ when I took that 314E back (as it was mono).
Check out some of my latest Deep sky pics for how well the 314L+ performs on my 1000mm FL 8" newtonian. I love it.
Cheers
Chris