I used to use Sharpservice, and it was great a year or two ago, but I had nightmarish problems with them on my last transaction (maybe 6 months ago?). They didn't respond to any of my emails, didn't have tracking information, in general didn't give me any communication for almost a month despite repeated emails from me. Finally I ended up getting upset in an email and made it known the extent of my unhappiness, and I got a call within 10 minutes from their UK office, and even though the guy was very abrasive we finally got everything worked out and he got my stuff sent out that had been with Sharpservice for several months. After that I switched to FromJapan, and it's been smooth sailing
Their commission is pretty low but there are also 2 "System usage fees" which are 5%. Commission for auctions are only 200 yen. I'm not exactly sure how it works with stores, but I imagine it's the same. Here's an image of one of my receipts so that you can see how they break it down. I know it's not what you asked, but I imagine people are wondering exactly how much it'll cost to proxy. This was for a relatively substantial knit.
i've always been unhappy with my tie knots, and i've never, ever bought a decent tie - finally broke town and bought a kent wang grenadine, and there's really no trick to getting an awesome tie knot. just need a thick ass tie.