Personally I believe that Google+ for your business is always a positive step forward at any time, Most business websites took years to embrace facebook and now you are presented with another social media site.
What Does Your Analytics Tell You?
Log into analytics and check what keywords are sending traffic to your website.
Is (not provided) one of them ?
What Does (not provided) Mean?
With the recent integration of Google+ and Search, when a user is Logged into a Google product and then searches for something, the keyword used to find that website is registered as (not provided).
The reason for this is that Logged in searches are conducted in a secure search.
If you want to check this, open another window and look at the URL, it should be http://google.
Then log into any Google product, your gmail, analytics.
Now open your Google search, the URL should now read https://google.
What Does This Mean?
This means that people are finding your site when logged in. The way to influence the search results when Logged in, is with Google+ and your circles.
Logged in Search or Search Plus Your World (SPYW)
The way to capitalise on secure search traffic is with Google+, this is where the people you circle (like) or follow (friends) directly affects the way a search result is provided to you based on personalised search.
So if you are unconvinced to the benefits of Google Plus for Business, take a look at your analytics and see what it is telling you.