imember360 support Google First Click which is a feature created by Google specifically for membership sites with protected content.
Google First Click gives full access to the protected page for non-members so you probably want to use this feature selectively unless you have a large amount of content on your site
imember360 supplies the i4w_show_gfc shortcode which you can use to wrap around the content that is available.
To maximize the success of this approach you should ensure that :
- the first click content is properly SEO'd
- the first click content should contain some form of upsell to encourage the visitor to access to more high quality content like this maybe via a sidebar ad or a popover ad
- the full content of the post available to member is consistent with Google's guidelines on using First Click
- the public content of the post is limited with an indication that this is restricted content
- you monitor your conversion rate to ensure this approach is working in getting new members