I'm a China supplier, I can answer your questions:
1. Global Sources Verified Suppliers, are they safe?
Global Sources request their China-based suppliers to pay a membership fee. So, these suppliers are mostly big suppliers and do not accept small orders.
But, I can't tell you if they are really safe. Looking for a reliable supplier is more important than price.
2. Is PayPal a safe way in China?
Yes, my online store also support PayPal. But you should be more concerned about the quality of the product