With MozLocal you're getting distribution to the top 4 data aggregators with one simple submission. I know if you go direct to just one (like Neustar/Localeze) they can charge you yearly and it's MUCH more expensive than Moz just for this one site. So it's still a good deal. Last time I checked it was like $300/yr. per location just for Neustar/Localeze.
Also, submitting to these services more than once is important. It shows downstream that you're still an active business and the sites can use resubmission as a positive signal to keep you in their listings.
I've done a lot of research and I've submitted to these services individually before. I've even paid to be a partner member with Neustar to distribute listings and MozLocal is the best and easiest way to distribute to the big four (and it will hopefully only get better with age.)
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