Your SG corporation will be a controlled foreign corporation.
Unless you are exceptionally well-organized and advised, the income generated by your company would start to look a lot like Subpart F income. Translation: all of the profit of the SG corporation is taxable to you as a human being, every year, on your U.S. individual tax return.
Now. You might say "Meh, profit is profit and if I have to pay tax what does it matter. I will have to pay tax anyway." Well, yes, to a point. But I will gloss over that or what I talk about will look a lot (to you) as snippets of code look to me. Unintelligible.
The real problem is that the U.S. tax paperwork burden is profound. And it is beyond the power of mere mortals to do it properly. You are in the realm of paperwork designed to capture transactions and operations of companies of Google's ilk. Not ordinary small businesses.
And if you screw up the paperwork, the penalties will eat you alive. E.g., Form 5471. This is where you tell the IRS "Hi, I am an American and I own shares of a foreign corporation." File late, and it is $10,000 please as a penalty. Don't fill it in right, and they say it is an incomplete therefore failed filing. $10,000 please.
Things start there and get worse.
The cost of running a SG corporation in SG annually is nontrivial. The cost of people like me is nontrivial. (I'm de-f'ing a SG corporation right now for a guy in precisely this position).
All of that money you save living in Cambodia will go to pay the overhead of your corporation. I don't recommend living cheap just so you can give $10,000 to someone like me. :-)
If you are an American and you want to live in a cheap country, kind of under the radar, and run your business from there, set up your company in the USA. Run it from there.
The probability of making a mess of international tax filings approaches 1.0 in a very few years. The probability of making a mess with domestic corporate or LLC filings is very low.
The cost of talent to keep your international corporate structure straight is extremely high. (I'm $750/hour and I'm not taking on any new clients at the moment). The cost of talent to run a generic domestic corporation -- you can get that anywhere from any random accountant and corporate lawyer.
That's my suggestion. Running away is the best strategy. Said Brave Sir Robin.