I have used the Staples multipurpose paper for years now and in all of my machines (copier printer fax) it has performed just fine. I also use Hammermill and as far as I can tell there is basically no difference. The brightness is fine and it appears to be a true 20 pound paper. It holds up doesn't jam anymore that any other paper that I have used and seems to age as well as any other brand that I have used in the past. So long as it is priced cheaper than the competition I will continue to use it.
This copy paper is perfect for my laser and ink jet printers. I have used many different brands of copy paper and this multi-purpose paper from Staples is the best brand and a great value. The brightness is complimentary of all of the copies I make for my classroom; it provides a neatness that some other brands do not. It seems much more sturdy than other 20 pound paper almost like it was 25 pound copy paper. The rebates from Staples make it most affordable sometimes it's free with a mail-in or e-mailed rebate form.