wiki says that - Asylum surgeon's ring - is members only item - so does that mean - re-playing it in free 2P - will not give this as a reward if I can under 37minutes ??
When a quest is free to play, it doesn't mean free to play and members all get the same rewards. Quite obviously, a member only Asylum Surgeon's Ring is not meant for free players.
I believe completing the 37-minute challenge will make it possible to claim the members-only ring when you become a member later on. (I've done the challenges in f2p, and plan on claiming the ring when I eventually become a member.)
I don't see why it shouldn't give you the ring if you do the challenges in f2p.
Just to add, you know the challenge to get the ring is the third in a series of three? The first two must be completed before the game checks if you completed the third, but they can all be done in the same run (if you're up to it).
https://runescape.wiki/w/Broken_Home#Challenges
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