Kowa 663 with either 20x wf discontinued, or 30x.Lighter than the Leica and to my eyes better image. Very close to my Swaro 65 hd.
I've had Leica APO glass side-by-side with my 65 hd and the Leica is as good, if not better.
The nod I give to my Swaro is the stellar warranty and larger, easier functioning focus wheel. The Leica is markedly lighter however.