We're running the onlineshop http://www.sabbs.ch and like your Relevanssi Search Engine a lot. It's definitely much better than the WordPress generic one. However we still face some problems. We think that results still include our description text for our products which often link to other products. Ideally it should only search for product titles, product cateogories, colour and the coolest thing would be if it would yield great results for search terms like "red trousers".
How can we achieve these results?
Many thanks for your feedback.