Do you refer to TMPGEnc Mastering Works?
I like TMPGEnc for many reasons, but quality is bested by others. AME uses the
MainConcept SDK, and it's really hard to beat the quality. You can do it with some extreme tweaking of x264 values, but not by a huge %. (I use both MC TC and x264 via Hybrid, but quality isn't the reason, the workflow is. Both are fine.) I have no reason to use TMW.
I mostly use TSR, for manipulating H264 files.
AME has always erred on the side of soft/blur, You can address that. That's probably the main difference. TMPGEnc is x264 based, and it defaults to less blur at the expense of other aspects.
AME is stripped down version of the full MC package you get in MC
TotalCode.