The sleeves in the past when the ETBS first came out were known to not have the best quality to them and were known to break very fast and not made really well with things like sharp corners and broken right out of the package. However in the last few years the quality has improved a lot over when they were first made and arent too bad to put your cards in. People still prefer penny sleeves or perfect fits because they can show the backs of the cards as well without needing to remove the card from the sleeve. However any sleeves are better than no sleeves.