I export as 16-bit TIFF, AdobeRGB (it would be nice if DxO offered ProPhoto as an option). I don’t use DNG because my understanding is that it’s not really a DNG, but just a TIFF in a DNG wrapper, and because I sometimes want to retouch the TIFF in Photoshop. After all that, I may then apply a few adjustments to the TIFF in Lightroom if needed (such as split toning).