I owned both and liked them both. It is sort of an apples and oranges comparison. The better depends on your priorities. The richer midrange of the Almarro over the Cayin turned out to be a deciding factor for the Almarro although I missed the dynamics and wider soundstage and raw power of the Cayin which still had a warm midrange and a great sense of presence.
However, you really haven't heard the Almarro 318B until you try it with some fantastic old stock Mullard brown base tubes. Myself and friends rejected the Almarro until the Mullards were put in, which was a complete turn around from the previous dull sound. The Mullards preferred by me are the brown base ECC33 (6SN7) and CV569 (6SL7/ECC35). I auditioned the famous ECC32 and 34 which were slightly warmer (a little too much so in my system), yet less dynamic and synergistic as the ECC33/CV569 combo.
However, you really haven't heard the Almarro 318B until you try it with some fantastic old stock Mullard brown base tubes. Myself and friends rejected the Almarro until the Mullards were put in, which was a complete turn around from the previous dull sound. The Mullards preferred by me are the brown base ECC33 (6SN7) and CV569 (6SL7/ECC35). I auditioned the famous ECC32 and 34 which were slightly warmer (a little too much so in my system), yet less dynamic and synergistic as the ECC33/CV569 combo.