In answer to the two question:
• The “default” exported version is quite old now as we’ve strived to avoid any breaking changes since the original launch. There will a major ‘2.0’ version released in the future that will bump these default versions to newer API versions.
• Yes, I would actively encourage the use of the explicit versions in the SDK as these should have much less impact between major versions of the SDK and will allows you to utilise new features ahead of them coming into the default version.