I have a XML sitemap set up for my website, which i made using Google Webmaster Tools. I don't however have a physical site map, for viewers of my website. What is the benefit of having one of these? Is it worth much in terms of SEO?
xml sitemap is used for better site indexing , but you want to provide better experience to your website user....you should use html sitemap
It is nice to have a physical sitemap for your visitors. It makes it easier to navigate your site and go to the particular page they are interested in.
Both type are sitemap is good, but not necessary. If you want to provide more convenience to site visitor use HTML sitemap and if want to give some convenience to search engine than provide xml sitemap.
Both are important sitemap for your website for the reason that XML Sitemap for Google or other search engine and Physical Sitemap for visitors