[US citizen] Nomura NISA account purchased SPDR S&P500 ETF (1557)

First of all, here's proof:

https://preview.redd.it/h4iffo1cbded1.png?width=1226&format=png&auto=webp&s=276eb8257b74f3d7e7920dd25267cd435b739b96

Benefits:

1. 1557 is not a PFIC. (Edit: Seems like some people are contesting this, consult with a tax professional if you are unsure.) (Edit 2: In addition to previous tax advice I had received, I just now called State Street Global Advisors Japan branch and they confirmed that 1557 is in fact not a JDR, but it is a cross listing, and they have confirmed it is not a PFIC.)
2. If you hold for over a year, any sales will be taxed in the US as long term capital gains. Not worth it if you're a high earner, but if you only plan on selling after retirement when you have near-0 income, OR you plan on naturalizing and renouncing some day, it might be worth it. (Keep in mind if you have exit tax obligation upon US renunciation, you may want to avoid selling the NISA stuff and sell other assets to cover the obligation increase from these NISA stocks… but exit tax threshold is pretty high, so only very rich people will be affected anyways.)

Some hurdles / caveats:

1. If you leave your JPY balance sitting there for too long, it will get auto-invested in a low-interest-rate PFIC known as "MRF"… I was able to get my JPY on there, buy, then move the JPY into the Nomura Shintaku Bank account that you get automatically when opening the Nomura account before it was moved into MRF… so I dodged a bullet I guess. But just be careful if they give you any distributions (even 1 yen). Their rate of return is so comically low, you'd need to hold millions of JPY for days maybe, but still… if you can move funds before they get transferred to MRF, that'd be best… transfers between Nomura and Nomura Shintaku bank are pretty quick during business hours, and free.
2. Orders for 1557 can only be done by phone in Japanese. I am not sure if they have English support for phone orders.
3. You can't order fractional shares.
4. Fees for phone orders are in general 2x percentage wise for a similar amount of online orders. For my order it worked out to about 0.68%, since it's tiered, the relative percentage rises and falls as you get closer/farther away from the edge of each tier, but around the yearly 2.4 million area it's about 0.7% ish. You pay a fee when you sell as well (also phone order only for now).
5. Nomura does not support 株式数比例配分方式 (tax free distributions for NISA, essentially) for foreign stocks that are traded domestically (including 1557). So even if your account is set to 株式数比例配分方式, they have a secret 2nd setting that you can only change via phone. It's "the distribution method when your main method is set to 株式数比例配分方式 but the stock you hold doesn't support it"… I don't think they have an official name for it, but it defaults to 郵便振替 (they mail you a voucher you can redeem at a JP Bank branch) and when I asked the lady on the phone about it she wasn't even aware that 1557 required any special consideration. I had to tell her what online support told me. "You need to change the setting for domestically listed foreign stocks because they don't support 株式数比例配分方式 but my account setting is 株式数比例配分方式, I would like it to deposit to my bank account please." and she eventually figured it out after putting me on hold a while. Distributions will have 10% withheld for the US and 18.2835% withheld for Japan (20.315% of the leftover), leaving you with 71.7165% of each distribution in your account every quarter for 1557. At current price and historical distribution rates, you should receive 1075 JPY per stock per year (pre-withholding), so you'll need to report that on your taxes.
6. This is growth-NISA only, so the lifetime cap is 12 million JPY, yearly cap is 2.4 million JPY. The phone order fee is included in the acquisition price, so you need to calculate the number of whole stocks that leaves enough room for the fee.
7. (Edit) As pointed out in the comments, Nomura currently does not have a QI agreement with the IRS, which is why I am able to buy US domiciled securities as a US taxpayer. There is a risk that Nomura decides to make a QI agreement and ask me to sell my 1557 holdings. Monex has done similar in the past, so there is a similar risk. This obviously should not be your only retirement investments.

Things I should keep my eye on:

1. If they ever support online orders (they might eventually *fingers crossed*)
2. If they ever get rid of the MRF stuff (a pre-requisite for the case if they start supporting 株式数比例配分方式, as I would not be able to move those funds out of MRF in that case.) However this won't be a problem if I ever naturalize and renounce.
3. If they ever support 株式数比例配分方式 for domestic traded foreign stocks. (JASDEC supports it, so it's possible, but just Nomura deciding not to as policy, according to support.)

Summary:

It was quite the pain going back and forth with online support to figure out everything before hand, but I finally got everything figured out and purchased. The lady on the phone order support learned a few things about her own company too.

Hope someone gains something from this!