I enjoy being able to see our 0 result search terms. This has allowed us to pinpoint what we are missing from our catalog as well as items we need to adjust wording on.

the backend offers a good bit of customizations

Having used various search/merchandising tools previously, including apps on other projects/eCommerce platforms, Klevu stands out because of its flexible nature when it comes to integration. Klevu's quick installation for Shopify Plus works well, integrating within the platform to get up and running quickly. Insights and merchandising are tied to the app, though I'm reviewing Klevu more so from a technical and development position. There's also a new "JSV2" product that allows for deeper integration into the platform, essentially allowing for complete control over the look and feel. For those using the standard Klevu functionality, I do like the functionality that the Klevu team has introduced into our setup specifically. Bespoke features - when it comes to algorithm and data collection, have been implemented quickly. The Klevu team overall, from support to client success, is solid. It may take some time for certain specific issues to be ironed out, but the team is dedicated and quick to respond to any issues.