I've been running my FADEC for about 4 years and about 450 hours. Here's how
I would reply:

HP:  Probably not significantly different.

BSFC:  I am almost certain that my EFI FADEC setup is better.  I can run
lean of peak without so much as a thought.  That includes through power
changes.  Also, the automotive world switched to electronic injectors
largely to improve economy.

CHT:  no change

Price:   more, until something breaks, then my parts (experimental) are
cheaper than aviation parts.  But then again, I WOULD trade my stuff for
certified if it were available (peace of mind that someone has actually
tested this in adverse conditions).

TBO: no change

Weight:  about the same, though my throttle body probably weighs less than a
carb, my coils weigh less than mags, but my two electric fuel pumps probably
weigh more than the mechanical and electrical combo.  And my wiring probably
adds more weight (maybe offset by lack of a mixture cable...)?

Other:  I don't screw around with mixture.  Ever.  It's LOP in cruise, ROP
in takeoff and landing.  I can switch to ROP at all times if I choose (by
flipping a switch).  That's nice.  Not certified - not nice.  No mechanic to
work on it besides me?  Not nice...

Matt