Has anyone used nenkin-japan.com? Is it a legit service?

I'm planning on leaving next summer and I'm trying to be proactive about the pension refund because it's a lot of money. I'm unsure if I'll be able to find a tax representative when I Ieave Japan (my current supervisor is leaving this spring and I'm unsure if the new one will be willing to help me with the tax refund or pension) and I don't understand the pension refund system at all, so this looks like a good option. Apparently it's ¥30,000 for them to basically do it for you. Has anyone used this and can vouch for it? Is it worth doing if you can't find a tax representative? Or is it a scam? Or is the pension refund actually way easier to do by yourself than I'm imagining and this isn't worth it?

by Beneficial-Corgi-288