[RobertGT]

Top loaders (all brands) are no longer the industry standard. They still allow way too much movement of the card, forcing you to buy penny sleeves just to keep the cards secure. Even then if you ship a card in a top loader, there is still a chance it will slip out the top when turned upside down and crease the card. It is for this reason that they are not accepted for grading submissions.

They are also expensive and heavy when you're trying to move a large quantity of them. So basically just to keep your card secure you have to 1) buy a top loader 2) buy a penny sleeve and put the card and sleeve in the holder and 3) put a piece of tape over the top of top loader before shipping.

All of these steps are consolidated into one by buying a Card Saver or the equivalent Ultra Pro holder. Plus your cards also look much better and more vibrant in them. I use Card Saver IIs for storage - as they will fit in any standard storage shoebox - and Card Saver Is for grading submissions.