A couple things I like about the Swarovski and the large focal ring (good when wearing gloves & fine adjustments) and the eye relief has a knob you can turn in or turn out as needed to increase or decrease eye relief. I wear glasses so that's a factor. If you wear glasses and look through many scopes at higher power, much of the field of view is gone without enough eye relief. Kowa has an eye relief of 11 to 18mm which may be a little tight at higher powers if you wear glasses. The new modular Swar scopes are over double the price of a Kowa which makes them way out of reach for me but the discontinued models/price puts them both in a similar price class for now. They're both great scopes. Haven't looked through the Zeiss so I can't comment on that.
I went with the ziess as I got a great deal on one and even though it was more than the sawro I was looking at the 75x was worth it to me. The kowa was just too expensive for me. Ziess has their field days with a 500$ rebate on the diascope. I get my ziess on monday and I cant wait to take it out in the field. In one of the later posts on this link Bitterroot Bulls does a quick rund down on the scopes Longrange spotting scope help!
