I've never directly compared SC and DH but when I made the switch, DH felt less artificial and more natural to me than SC. I've said this before but I never found a setting in SC that felt "right". My yamaha was a little bit older than the ones I've seen talked about here though and had less SC presets.
A TS plug doesn't have to be directly connected into the xbox controller for it to work, as long as a mono adapter is somewhere along the chain of cables you'll have no problem with the xbox getting audio from your mic. I've had a mic connected to a mono-stereo adapter then to a stereo 2.5mm-3.5mm adapter (for cell phones) and it worked fine. I dunno, it's weird, but I used that setup and other cable/adapter variations for about 2 years before I ended up just buying a mixamp and I had not issues whatsoever during that time.