I came across a good article on orchids and perlite recently:
Simply Hydroponics – Orchids
Mind you it is still quite subjective.
I use a combination of lecca, perlite and pumice in wicking pots.
Each has their own unique properties. I wouldn't really use any by themselves but in the right mix they work great.
Iecca is the airiest and should be used for dry pockets.
pumice is the most wicking. Like pumice will even suck moisture from the air if its humid enough and provide the roots with moisture. It's like a sponge. Too much of it has not brought me any benefits but using a little in a pot can help suck moisture from the bottom of the pot to the top. With certain mixes it drains to the bottom and the top dries too fast so pumice helps.
perlite traps moisture but stays airy at the same time. I use it for seedlings that can't dry out mostly or if a pot dries out too fast.
The main disadvantage I have found with pumice is that it degrades. It isn't quite inorganic like lecca or perlite which will last years and years. pumice I find can degrade like bark and after a couple years if kept too wet can crumble and might need replacing.
I thought pumice lasts as long as lecca but it does degrade. It is quite expensive when you factor in that it isn't forever lasting, it's pricey to start with, then I always have to pick out rocks and sift out the sand in the bag. Then it all needs to be washed. Ok lecca needs to be washed too but it is far less hassle than washing pumice.
I'm using less and less of it, that's not to say I will stop using it, it's just if you use less in a mix, it stays less moist over time and lasts longer.
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