I ordered the business cards!
They were really, really good. Better than any I could have made myself- and what’s more, it was really nice to be able to get them for free (besides P&P). The quality is really good and they actually arrived much, much earlier than I was told they would. You can also edit the card before you have it sent off, perhaps to reword it, add pictures or change the colour. When I went to my last art sale, they were snatched up like a storm and loads of people were showing a lot of interest in Fiverr itself, so it’s really good for promoting the site, too.
I suppose you make a good point with the fiverr profile promotion, but that’s the chance you take, I guess. Some of the people who got my business cards bought from me, and some didn’t. Whether that’s because they didn’t want to bother to sign up or not is beyond me, but it’s still nice to see that it’s good for spreading the word!