I have the feeling that the component input of the HD system is not quite right. The images look darker after being digitized than with the M100 I system. Worst is that i feel like the signal is a bit destroyed like it was at the time of the 601 card when we use it in 720 (square pixels) instead of 768 in Pal mode. It's a real problem for me because i use a lot of DVCAM digitized in component (i don't have decks with SDI output). Am i dreaming, am i alone ?
Look at color bars with scope/waveform. bump it up and down tape a few times and check again. Mistakes will show up.
If it's possible (have no idea about current versions) check if your capture settings are all default.
If going a few generations shows offset, try it with another deck that you know is good. If the same offset occurs, your M100 is wrong. Alter the settings with 10th generation material so that the bars show correct and divide those values by 10 and set that to your capture settings.
Dunno about the distortion. A simple wipe with a vision mixer will tell.