Love my Kowa 601 and 663 spotting scopes, but do not like the TE 9z zoom eyepiece. After extensive research and talking to the experts, I think the Opticron SLDV3 should provide the best upgrade for these scopes. Looking to buy or even rent one of these eyepieces to try on my Kowa spotting scope. If it works out to be a nice improvement over the TE 9Z, will design and machine an adapter for the Kowa scopes and make available to others that are in the same boat. Anybody have an eyepiece that is interested in selling or renting, PM please. Thanks.