I prefer to use the poly-lined paper sleeves for my records.
Now that you mention it some of my quietest records are 30 to 40 years old and have been in their old original paper sleeves all those years. If they are starting to deteriorate and turn yellow, or the edge of the record has cut through a side, I'll replace them with Bags Unlimited poly lined paper sleeves. Those are good ones.I use the originals unless they are in obviously bad condition. I haven't had any problems with doing this in over 40 years.
Doug
Id say depending on how many you need, id say go for the disc keeper if you need more than 300, I need to to order about 500 inners and outers, going to get the 5.0mil outers and the ultimate audiophiles.
I use Sleeve Town's 2.0 Diskeeper antistat poly sleeves. 9,000+ LPs are cleaned and in them. Once cleaned and in these sleeves, static problems disappear. Which is saying a lot as I live in a very arid location.
What sleeves do you prefer? Paper, rice paper, poly-lined, round bottom, square, etc? Links to sources welcome.