Letgo is like CL with screen names and avatars. You are still meeting someone you've never met to buy/sell something. I've used both with the same end result. Just be careful where you agree to meet.
Used both letgo and craiglist with moderate success, but their reach is limited. Hot items sell fast; otherwise you might be waiting for months before you get a bite. Both will end up with a fair number of time wasters who message you but never reply.
At least letgo has built in chat so no phone number/email trading needed in most cases. And users can be rated and verified to show trustworthiness.
Moderate success with it here as well. Like said, it's step up from CL, but not as "good" as FB marketplace IMO. At least with marketplace, you can check the individual's profile. See if they're local, etc.