Is alibaba paypal link: paypal.me/(something) legitimate?

[Irina_S]

A new alibaba supplier has provided me with this link so I can pay for a sample of their product. 

This is the first time I'm paying through Paypal. They said using Trade Assurance, Alibaba's protected payment option, means they'll be charged a fee and it's too much for the sample that I'm getting.

I understand that, but I want to make sure I canprotect both the purchase and my money. If the link is not legitimate, what info do I need to ask for/provide so I can make the paypal payment safely?

Thanks.