Bienfang is an old, well respected brand of art and office supplies.
A buck a sheet sounds a little expensive, however. I have been using the Arista brand tissue from Freestyle - 8x10 is $16.99 for 100 sheets, or 17cents/sheet.
There has been a lot of discussion about using mounting tissue with a hand iron. Even Ansel Adams mentions that in one of his books. My experience with that was very unhappy - I couldn't get the heat to be even enough to avoid bubbles between the print and th emount. Eventually, I found a used dry mount press (a 12x15" Technal, $75) that I am still using, 20 years later.