They are saying that using perfect fits + hyper mats for double sleeving is good for playing, but not for storing valuable cards.

DOUBLE SLEEVE NOW! Some important things to note WE CAN DOUBLE SLEEVE NOW! Some important things to note

A diverse community of players devoted to Magic: the Gathering, a trading card game ("TCG") produced by Wizards of the Coast and originally designed by Richard Garfield. I am asking specifically in this group because I want to know perspective from financial point of view (as I am collector, not player)Can't really seem to find the exact sizes of the penny sleeves, covers, and/or toploaders. Mainly the sizes of the cards that it is able to hold.

The Professor rates perfect fits : r/magicTCG - Reddit The Professor rates perfect fits : r/magicTCG - Reddit

And I am always open to receive advice for better protection in terms of (double) sleeving and or preserving cards with an eye on all potential forms of damage (water damage especially, but also scratches, dust and so on) After that, i choose to use only inner sleeve ,without double sleeve , and i had 3 option, kmc perfect fit, kmc hard fit and Dragon Shield Sealable. Each of them have their pro and cons, this is the review and the votes of what i understood: For protection purposes I would like to double sleeve my cards by using the Premium Standard sleeves from Ultra Pro, then put them in the Standard Sleeve Covers from Ultra Pro, to then put them in an Ultra Pro Toploader.keep the cards at their best possibile condition for years ( prevent them from dust, curling etc ); I’d like to start by warning people looking to buy inner sleeves: do NOT buy any side loading inner sleeves! These could potentially damage your cards in the long run, as there is still friction between that side edge and the outer sleeve. This is a minor issue and probably won’t be super relevant, but it’s always an important thing to note. Thanks to new yugioh policies, we are able to double sleeve cards so long as 1 of the sleeves is clear. This is amazing news, since double sleeving is great for protecting your collection.