Hi Matthew,
It might be worthwhile seeing what people have been able to produce with the new ASI camera :
http://www.astrobin.com/groups/31/
IMO CCDs still have the edge over CMOS when in comes to DSO imaging, but CCD-based astro cameras are also more expensive. If it was me and if budget would allow for it, I would be seriously tempted to grab a camera with the 16200 chip.
But as it has been already mentioned, a good focuser as well as the cost of filters and FW all need to be taken into account as well.
I'm sure you will have fun with whatever dedicated astro camera you choose
