it is heavily dependent on filters and telescope used. It's like with parfocality - you may have parfocal filters (yes they really exist), but in praxis you never have parfocal system unless you are imaging with reflecting (mirror) telescope only - i.e. without any refracting element like focal reducer or flattener or coma corrector. So in real world, there doesn't exist a parfocal imaging setup.
Back to weight factors - Astrodon does have I-series for Kodak KAI detectors and E-series for Sony ICX and Kodak KAF detectors. I do own both sets as I own both types of CCD and the RGB weights are really close to 1:1:0.9-1.1, but it always depends on your skies and where you are imaging blue channel - wheter 50 degrees above horizon or lower where refraction occurs which kills the 1:1:1 TruBalance.