Am thinking about putting one of these on a big bore lever action. Any opinions as to advantages of one over any of the others? I have zero experience with any of these sights. Your comments are appreciated. Regards.

I would recommend the Docter if it MUST be a red dot... Some great mounts come here:
http://www.titanium-gunworks.c...ter-sight/index.html

But there is the question if a red dot is the optimum? For me not.

Ever thought about a led illuminated front sight?
Check out this:

http://www.titanium-gunworks.c...ht-daynightfire.html

The virtues of the big bore lever guns are their short and range quick handling. Optics detract or counter them so I am for anything that improves or enhances the primary virtues. I would lean towards the most robust, repeatable & reliable.