My last HP was an Office Jet Pro 8500. The main problem I had with it was repeated and frequent print head failures (it uses printheads separate from the ink magazines. Replaced under warranty and a couple of printheads failed again after about a week. "Warrenty replacement" printheads crapped in about two weeks.

Junked after a couple of months of trying to make it work.

My current Epson WF 7520 is a "Workforce" series intended for moderate to high voume "office use," and handling B size (11" x 17") paper, while your HP Photosmart 7520 is a "letter size photo multipurpose." Not much similarity. Your HP 7520 is more like my Epson 2540, except my 2540 has been trouble free for about a year so far.

There's only so many 4-digit numbers available*, and the marketing guys say "4-dgits is more impressive that 3" but "nobody will remember anything with more than a 4-digit number," so some similar model numbers are probably inevitable - but entirely coincidental.

* Toyota would have been Toyoda if the numerologists hadn't objected when the "brand" was about to be first introduced. Waitng for a date compatible with the "number value" of the original (family) name would have delayed the release by several months so they "picked a better name."

John