How are you processing them? So far I couldn't get any usable results from CHDK RAW. I'm also using an A570. Converting to DNG and using Adobe converter works the best but still sucks. I'm used to Nikon DSLR RAW workflow and so far I don't see much benefit in using CHDK RAW, at least for my camera. Each picture would need extensive work to even compare to in-camera jpgs.
From what I understand the best mainstream converters (Bibble, CaptureOne, DXO) do not and will not support either CHDK RAW or non-native DNG.
I am still saving the RAW files hoping someone eventually develops a solution.