Guarantees/warranties are also part of the overall picture as are weight and handling with the expensive well known models Waterproofing for one in the UK is often a help and added safety factor to allow more varied useage The Swarovski El's and other top marques do offer many other non image based attributes of course and demonstrate i believe what can count in addition with the high end binoculars I personally find the view very similar to Swarovski 8.5 x 42 EL and felt it was a close thing over several hours of comparison with a kind fellow birder In summary i think for aome folk the Jenoptem's are fantastic value and produce an image that is relaxing and wide in use The Carl Zeiss Jena's are my favourite overall both for airshows and low light viewing they are the brightest but both Nikon's seem to offer more contrast also the Jena's have limited eye relief and are a little less sharp to edge (though imho this is negligible in quite a lot of terrestrial viewing) The SE Nikon's are very well constructed fabulously sharp and true to almost the edge but are a little awkward for eye placement and black outs can occur also slightly limited fov at 6 degrees The E11 seem the widest angle and overall probably the easiest to actually use also pretty well built

I own and use Nikon E11 (8 x 30) Nikon SE (10 x 42) and Carl Zeiss Jenoptem MC 10 x 50

Carl zeiss jena binoculars df 6