I had read a lot of negative reviews about jlist, moreso on other sites than here, so I only made a relatively small order to see what my experience was like before committing to a larger stash of all of those fantastic goodies they've got on there.
So, I purchased:
A bento box
An absolutely adorable bag for that bento box
Some cute cup things to go in it
And
Their Popin' Cookin' Gummy Sushi Set (how could I resist?)
I think all of these things were reported as "in stock in Japan," but I think that perhaps the Popin' Sushi one wasn't. But anyhow...

It took about a week for my order to ship, which would make sense if they were waiting for my one item to come in as my instructions were to wait until all of my items had arrived before shipping rather than ship in separate orders. Then, two weeks later, the items arrived at my doorstep. I was away at college, so wanted to wait until I had seen everything before reviewing, but I've looked everything over and it's all just fine, and just what I wanted!

I used the cheapest shipping method, as well, so I wouldn't have been at all surprised if my items took me 3-4 weeks to get to me after shipping a bit late. But nope, the whole transaction took about 3 weeks total, which, all things considered (namely the fact that international shipping ALWAYS takes longer unless you're one of those people that does all they can with their mailing choices to make it super-express) is okay with me. I now have an adorable start to my bento box hobby!

So, I never had the need to contact customer service, so I can't say anything about that. But the fact that I didn't need to is pretty great too. I'll definitely be going there again if I can't find the bento stuff I need at a more local place, or just in general if I want some cool bits of Japanese culture in my life!