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K Andy is correct. The practice used by your competitor is outdated and against google guidelines. From our experience we often see (looked at one last week) exact matching domains rank highly without any other metric being strong or comparable to competitors. However it is counter intuitive as if you were today to buy an exact matching domain and then expect it to rank well without hard work - well it simply does not happen anymore. They seem like relics, and panda updates have passed them, likely thin content as well. For some reason often exact matching domains that breach google guidelines still rank well - in my observation in low competition spaces. Your examples are all local.  The key is not to attempt any bad practices, even though they are ranking for them as it will hurt your site. So in answer to your questions. 1. It is not good technique - in fact usually penalized. 2. content spinning is not a good technique - in fact usually penalized. You have an awesome opportunity.  One dedicated site with a single site approach. As distinct from his 4 sites. All work undertaken on your site (Creating unique content, testimonials, obtaining awesome links) goes to benefit all of of your store locations at once, if your site is well structured. Your website obtains maximum 'juice' out from your hard work and the site authority strengthens over time. You can smash those 4 sites with a bit of work. Hope that assists.

Thank you Tom for your comprehensive answer. Indeed, we are experiencing some drops with backlinks comparing to the beginning of the year but I don't think it's the matter of penalty. The main source of incoming traffic is our publications, PRs, a few discussions and since we have a pause with publications that can be a reason for a drop. Back to the matter: yes, we are updating company and product branding, keeping our value proposition as before, just making a stronger statement. And yes, I'd say I'm more inclined to the idea of keeping the domain as it is and publishing the new website there (of course with 301 redirect for old URLs) but many industry colleges suggested to create the subdomain for the "backup" purposes "in case if God knows what happens you will still have your old website structure". Thanks again for your point of view, will definitely consider it.