It's very durable and each and every part can be repair.

Judging by all above ignorant negative comments, how many of you really owns a genuine pair remains to the question. Sour grapes. If u don't understand and can't afford the high price for such sandals, suggest u to dig some research before making a fool out of yourself.
Regarding the "this shoes meant for indoor" comment, I find it hilarious. No European slippers or sandals are specially made for indoor or outdoor purpose. Just wear it whenever and whenever u like. Birkenstock comfort emphasize on arch. It is design to fit perfectly on your feet. Not for cushioning purpose.

Extremely durable. It's not water proof. And most expensive shoes are not. Hot weather wise is also non-relevant. Don't forget, there are few months of summer all over the world. And the heat can be higher than Malaysia. Oil application, I haven't done it, so no comment on that one. It might help applying. But I had mine for 4 years and counting. Love it.

Not sure if Birkenstock owners here really wear it with such cautious in mind. At least not me. It's a slippers bro. Not a phone.
BTW, don't think u want to wear any slippers for hiking either.