A few months ago I replaced a Nikkor 70-200mm f/2.8 VR w/ a Sigma 70-200mm f/2.8 EX G HSM, mainly due to financial reasons but partially for weight and size reduction (the Sigma is the same length w/ hood on as the Nikkor VR w/ hood off). I've been shooting w/ the Sigma for a few months now and I've been very happy with the sharpness, color, and especially the handling and balance. Now I need to get around to replacing my TC(s). I had Kenko DG 2x and 1.4x but neither will work w/ the Sigma. Now I need to pick up one or two that will work with the Sigma. My Sigma is the HSM D version, not the DG and I'm shooting with a D50. I was planning on picking up D model TCs to save some $$ and to match my D lens. Now I'm reading at KEH that the D TCs will work with film only and I'll need DG TCs to work properly with digital. Is this true? Is anyone using Sigma D TCs w/ digital? Or will I really need DG TCs even though my D (non-DG) works perfectly fine on my D50? Thanks!