Is performing Sa'i on the second floor less rewarding than performing Sa'i on the ground floor during crowded times, and is the reward commensurate with the hardship?

Performing Sa'y and Tawaf on the upper floors is rewarded, and the proof for this is the Prophet's (peace be upon him) saying to Aisha (may Allah be pleased with her): "But it is according to the extent of your expenditure or effort."

Performing Tawaf and Sa'y on the upper floors is permissible. In cases of difficulty, performing Sa'y on the roof of the Masaa is more akin to fulfilling a ritual of Hajj or Umrah than performing it on a camel or similar animal. The majority of scholars and some Shafi'is have permitted performing Sa'y and Tawaf on the upper floors.