A viewer opens photos. Culling is a workflow.
XnView MP is genuinely good at what it is: a broad viewer, browser, and batch converter that handles hundreds of formats and costs nothing for personal use. That is real value, and we will not pretend otherwise.
But culling a card of a few thousand frames is a specific job, and a general viewer is not built around it. That is where we come in. Our app is called PhotoTaken, and it is built to do only this: rip through a contact sheet, rate and reject, keep RAW+JPEG pairs together, and move on. Your ratings and color labels are written to standard XMP, so every pick travels straight into Lightroom, Capture One, or whatever you edit in next. No re-tagging, no lock-in.