The short answer is yes, very. But you must be prepared for a long-term investment, of adapting your site to the requirements of the search engines and to the needs of your potential clients.
SEO isn’t just “build it and they will come” (to quote a famous movie), no its about doing the right things consistently. It’s about search intent and ease of navigation for your visitors. Get it all right and the benefits far outweigh the pain it takes to get there.