Test drive 5: Cariama
Not actually open yet! So. That was fast. Somehow someone has listed 1 item (maybe a test item in some manner?) but otherwise, this isn't running yet.
Test drive 6: vitty
I am guessing vitty's having issues with the influx of people, I'm incapable of getting a box delivered to me to try a listing. However, looking through the help docs, there is no bulk listing feature at all, so that kinda excludes it as an option for me. Additionally, I'm not fluent in Japanese (and not even barely literate), so as it's a Japanese site, I would be excluding most of the audience by being unable to list in Japanese. The website itself is set up well for English speakers though, and for people looking to expand into the Japanese market, I think this would bear looking into just for that.
Additionally, there's no commission at all on any item under 51L, so it would be a great market for cheap promos. (Standard 5% on 51L and up)