"So you can use any ATM with Visa logo in China to get RMB out? Then the US $ is taken out from your Schwab checking, no ATM fees both sides and no foreign transaction fees?"
Yes, no added fees by the banks on either side, though there is a Visa network charge built into the exchange rate. Also, if you're in a country like Thailand where the local banks do add an ATM fee, Schwab will refund it.
Note some cautions with Schwab:
-- They are first and foremost a broker, and offer checking accounts as an adjunct to their brokerage business. If you just want to open a small checking account to take advantage of their no-fee ATM cards, they may not be eager to serve you. They expect to make money from you as a brokerage customer. And if you do a Google search, you'll see some complaints indicating Schwab does from time to time close accounts when their activity doesn't meet Schwab's business model.
-- Given that the securities business is highly regulated, as a broker they seem very sensitive to accounts with a lot of non-U.S. activity. Using a VPN when checking your Schwab account and not using foreign ATMs too frequently would be a cautious approach. Or you can open a Schwab international account in Hong Kong.