While I agree that a cooled CCD is a vast improvement over an uncooled one, my experience is that the DSI-Pro is not quite as bad as you indicate. Adding a fan to the DSI-P helps things considerably. And as you say, using it during the colder months of the year is a good idea. I used a DSI-P for a couple of years prior to upgrading to an SBIG 402 camera. With the DSI-P, the normal dispersions in the data of 8 to 10 Mag variables was about 0.05 mag. The best I every got was around 0.03. That being said I still plan to use the DSI-P for the upcoming Eps Aur campaign since that variable is so bright it tends to saturate the SBIG camera.

Attached is a graph of a Landolt Standard star taken with both the SBIG 402 and the DSI-P. You can see the dispersions are much greater with the DSI-P. However, this still means it should deliver pretty good results on brighter variables, especially during the cooler months of the year. And of course, good dark skies always helps (wish I had some).