Re: General scope quality question
Let me start out by saying I am in no way an optics expert, but I have learned a few things about the topic, some here some the hard way.
Basicly there are two major areas of concern in a scope, the glass/coatings and the mechanical adjustments. You can find mid level scopes that have tolerable glass/coatings and you can find mid level scopes that are fairly repeatable. You'll be hard pressed to find either in a cheap scope and to get both you start to climb into the low end of the upper class price bracket. (if that makes scense)
To get a scope that is repeatable each and every time that allows you to see during the last bit of daylight you need to go with a name like Leupold, Zeiss, Swaro., Nightforce, something along those lines.
Hope that helps some.
Ignorance can be treated with education, sadly there is no cure for stupidity.