Question is is the price difference worth it?
Only you can answer that.
From your post I get the idea money is not a limiting factor with your purchase. I have a Swarovski z5 5-25X52. During the daylight it is not as good as my Bushnell 6500 4 1/2-30X50. What I mean is if the z5 needs 10X for me to see detail the 6500 needs only 9X. When in low light it is about the same as my two Bushnell 4200 4-16X40's. For example if the 6500 needs 10X the z5 and the 4200's can show me the same detail set on 7X. Functionally the z5, although it starts at 5X, has a larger field of view than the 6500 on 4 1/2X.
I purchased and returned three z5's before I kept the one I have, which is #4, because the others were not as good as the 6500 at all. The reason I kept trying with the z5 is because it goes to 25X and I hoped would be better in low light; which this one is and it is lighter than the Bushnell.
You should certainly buy from a company which will allow you to return the scope for a full refund if you do not like it. The Bushnell Elites come with a
full year satisfaction guarantee; even after you mount it.
If weight is not a problem for you, maybe start with the z6. I am totally ignorant of their quality or shortcomings.
By the way the 5-25X is only about one ounce heavier than the 3 1/2-18X.
