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I have about 25 pages on my website and after seeing Matt Cutts talk about how keywords in a URL is a good SEO technique, I decided to rename my files a more SEO friendly name.
However, I now have many urls (9) that include the keyword "ninja-warrior" (i.e. ninja-warrior-gyms.html, ninja-warrior-training.html). Is that considered stuffing?
In addition, I would have to use 301 redirects as I'm changing pretty much every url on my entire website.
Evaluating those two concerns, are the SEO rewards of keyword friendly URLs greater than the risks of losing link juice with 301 redirects and possibly getting penalized for keyword stuffing (if that is possible in this scenario)?
Note: There are a couple similar questions, however I am asking more on a risk vs. reward basis including the downside of having to use many 301 redirects which hasn't been brought up in other questions. It seems this is being perceived as a duplicate.