I do a quarterly newsletter mailing and the price increases have sent me to the swap meets to find a cheaper envelope. This is way too much of an increase this year. Sometimes the envelopes are coming apart and the closure can cut like a knife. Self-seal ones are even more expensive so that doesn't help our group.
For personal use I find these envelopes to be great. It helps out to send all size letters with less or none at all creases in the letters or papers being sent.