Genziana is made by infusing gentian root in Nardini grappa, in turn made with pomace of grapes from vineyards of the hills and foothills of the Veneto...
I have not tried Suze and Salers yet. From the way they are proposed in cocktails, I suspect they may be sweeter products than this Nardini gentian-infused grappa, which is indeed very dry. Nardini Genziana may not be an alternative to those two Gentian liqueurs.