The Bushnell Banner 3-9x40mm is an inch shorter than the Nikon Prostaff 3-9x40mm, however, the same weight. The Nikon Buckmasters ARE very long. I find the Banners and the Elite 3200 to be compact.
1-4x and 2-7x scopes often find homes on top of leverguns, I've just never found myself drawn to such low magnification optics. The FOV isn't a problem for me, and personally, I prefer more magnification over less.
One thing of many which sways my preference for a bit more magnification optics on revolver cartridge carbines is the extreme trajectory. The more magnification I have, the better I can estimate my hold over. "Aim small, miss small," as they say - if you can't see closely enough to pick a precise point of aim (POA), you can't ensure you're actually placing the bullet precisely. Having a little extra magnification helps the shooter better identify his hold over. If the body of a whitetail deer is only 10% of your FOV (which is what a whitetail at 100yrds covers in a Bushnell Banner 1-4x), can you REALLY tell whether you are you holding over 10" instead of 14"?
To give you an idea of the scale of the Bushnell scopes, here's a pic of a buck I took with a Bushnell Elite 3200 3-9x40mm on a Marlin 1895 Guide Gun 45-70. With factory Hornady FTX loads, it tracks just a teeny faster MV than a 44mag - 1792fps. This shot was 250yrds, which means 30" of hold over to get on target.
Here's a pic of the same rifle with a Nikon Buckmaster 4-12x40mm on top. You can see the difference in length - In both pics, you can see the magnification ring sets right above hammer for both scopes, but for the Bushnell in the pic above, the objective lens ends behind the rear sight, whereas the Nikon below (not really fair comparing a 3-9x against a 4-12x) hangs clear over the length of the rear sight - looks like 2-3" longer. You can also use the checkering as a reference - the 3-9x Bushnell barely hangs out as far as the checkering, whereas the Nikon hangs a LONG WAYS over the checkering.
EDIT: I measured a couple of my scopes, my Bushnell Banner 3-9x and Bushnell Elite 3200 3-9x are both 11 1/4" to 11 1/2", whereas the 3 of my Nikon Buckmasters I measured (4-12x, 4.5-14x, and 6-18x) were all 14 1/2" to 14 3/4", with the caps in place. So yeah, the Nikons are about 3" longer scopes than the Bushnells.
The Elite 3200 has the best glass of any on the above list. The only reasons we replaced it with the Nikon Buckmaster on my wife's 45-70 in the pics were to gain finger adjustable turrets and side focus parallax correction.