Listia started out really well, but over the years they haven't been able to stop the inflation.
I joined when they first launched and loved the idea of trading items in a cashless economy where we're helping each other out. As time has gone on, there has been rampant inflation from the value of credits going from 100/$1 to 10,000/$1 to 40,000/$1 and now finally landing at a 27,500/$1, but it is fixed by Listia.
So buying/selling credits is fixed to 27,500 per $1. However, you will NOT be able to find any gift cards selling at that rate. Every gift card, including the ones sold by Listia, are around 100,000 credits per $1. It's the type of economy where there are winners and losers, and the losers are losing because they do not realize when they sell that they won't be guaranteed that their credits have the same value. A little inflation would be understandable, but 100=$1 to 27,500=$1 is a bit wild.
The site does have certain categories with a lot of selection, and if you make sure to pay attention to the credits' real value you can have some good deals here and there, but nothing like the old days.
I'll keep using it, but I've started using other sites like eBay, eCrater, SwapCaps, etc. Still hoping for a site like Yerdle (closed down) and the old Listia.
Bottom Line: No, I would not recommend this to a friend