Tony or Paper will most likely be able to answer this better than myself but it is my feeling from looking at local results here, I would say Google plus is the best option to have a web presence without a website at all if that is your only option.
For example in my area, metro orlando, if you type my city name and sod into google, I come up on the first page organically and in google places. To me google places plays such a big part in many searches because between places and the first three ad spots that is the first 50 percent of the first page. Here on the search for my towns name and sod ...on google places four of us have websites...the other three do not just google plus pages.
Organic search results are still important do not get me wrong as I am working my tail off to rank higher and higher on many terms...but the fact is that if I was to be on the google places maps for all those search terms I would guess it would generate just as many leads because almost any search keyword now results in two or three paid ads on the top of the return from google then the next seven are google places map business listings and by then you are generally well over 50% down the first page.
In a related note without a web page..do not forget to register on bing/yahoo maps/places as well.