I think we shouldn't really refer to comments from users in Singapore in this case.

1. We are mostly using single-split units, while they are mostly using multi-split units. The first link you've posted complains about the noise of a multi-split compressor. I don't think it is too relevant to us.

2. In the second link you've posted, it is clearly an installation issue where the copper pipes are leaking. Nothing to do with the quality of the air cond.

My current house as well as my brother's house have been using Sharp air conditioner for quite a while. So far they are pretty good. I will be using Sharp inverter air conditioner in my new house as well.