Crane has built an image that is second to none. In fact, I would choose their paper just because it has the Crane watermark in it. The lettering is flat, not raised, because the ink dries into the paper. Offset printing is perfectly acceptable and, depending on the ink colors and the paper you choose, can create a handsome letterhead. This is the process of creating raised letters from plastic.
Lawyers often order thermographed lettering mistaking it for engraving.
Personally, I don't like thermography because it is shiny, reflects light and looks like the letterhead your plumber uses. It's more expensive, but done correctly you can't beat the appearance. Engraved lettering is raised, too, but the letters are dull and do not reflect light. The ink dries on top of the sheet and you can actually chip off the ink with your fingernail. One downside of engraving is that the letters have traditionally been fuzzy around the edges and not as precise as printing.