This is just my opinion and I can't really support it scientifically, but from the games played at the last TCEC I had the feeling Komodo plays really great in KID and similiar structure positions. I think it was mainly outplaying Stockfish in this type of positions. It feels very well the positions for knights.
Stockfish is not really great positionally in my opinion, but it is the one calculating the deepest, so it's great at finding Zugzwang positions, and breaking fortresses.
Gull is very strong at simple, almost endgame positions, and drawing little worse endgames.
Actually I always felt houdini is the strongest positionally, it just can't calculate so deep like the other ones, but it's just personal opinion. It is the best to evaluate positional pawn and exchange sacrifices.