"is between" operator option?

Yeah my mind boggles how something like that would work, it certainly isn't a case of plugging in a slightly different sql pattern like you can with all the other match operators, this would explicitly treat both fields as being part of the same equation.
It just doesn't fit into the design of the module :/ And like I've said in the other issue I don't think it would fit into how most people would need to use range matching.

Unless you can suggest a patch of how this might work, I don't think anything will be done about this. Finder is annoyingly complicated because of the ability to accept multiple values and search on multiple fields, and then depending on where the tables/fields are in the database and how they are related things can get really tricky, so anything like this has to work in all those different kinds of configurations. I'm not saying it can't be done, but it isn't a good sign if I can't confidently think of a strategy that I'd be happy to maintain.

I'd like to make an attempt at reopening this and see if anyone wants to take this on, as I think it's a pretty important feature for finder. In my case I need to have a dropdown for square footage options - 1000-2000sq feet, 2000-3000 etc - two dropdowns each listing 1000, 2000, 3000 etc would also be possible, though i think that could cause errors if someone selects 2000 - 1000.

That said, for anyone else that needs this feature and finds this page, I have found a workaround. It's a bit tedious for the admin and somewhat more limiting, but it should work (i'm going to implement it now). Add a new field to the content type that has a dropdown with your desired value choices, but don't display it. Do the same in your view (field added but don't display). The admin will have to both type in 1250 and select 1000-2000. then you can have a dropdown in finder to select between the various filtering options. This is going to be my approach until it's supported in Finder.

Please refer to #3