Comparing these two machines is like apples and oranges. They are of different class.
Tiger: extremely heavy, slow, big gun. Used as a breakthrough tank, or a glorified AT bunker (well, that's a somewhat stretched description, but you get the idea).
Panther: medium tank; primary role - to exploit breakthroughs. Medium gun and armor, good mobility.
IMHO, Tiger is a mediocre example of heavy tank class (too big, too heavy, too expensive, logistics nightmare, crappy mobility, 88mm not big enough HE for a breakthrough tank), while it is a matter of taste to decide whether T-34-85 or Pz-V is better medium tank.
Surely enough, as a semi-mobile AT bunker, the Pz-VI was a large threat to soviet tanks. However, it was very poor "value for money", if you see what I mean.