The only trouble I had with these envelopes was getting them open--then I discovered an easy way to do it by pinching the two faces together and slightly twisting. The size is right for letter-sized items, and they still seal even if trimmed very close to the edge of the document. Even with an inexpensive second-hand laminator the documents come out exactly as I want them.
I was worried about using any alternative brand pouches in my beloved Scotch laminator as a teacher--but they work and with only a very slight thinner difference that doesn't sacrifice quality/barely noticeable. Serves its function well; I recommend.
It's a good machine, cheap but does it's job well as a more expensive one does. Paper gets jammed once in a while but i don't think you can find much better.