Avid is outflanked in many regards in ‘assistant editing’ features: multicam functionality, syncing, exporting to various formats, etc. When starting a project it can seem like a daunting task begin your work in Media Composer. It’s going to take longer to ‘start’ editing in MC, often times.
But if you focus your attention on just the actual editing, Avid is the smoothest and fastest.
For the record, I’ve done lots of high-end FX and grading in MC. It’s far more than just a cutting tool. For compositing, though, it’s usually an awkward choice due to its layering structure (again, exceptions exist).
For me, Avid will remain part of my arsenal no matter what. For anything longer than a week’s worth of work, it’s still my top choice.