I recieved my Alpen Raineer 10x42's and compared them with my Zeiss 10x40's today for about a half hour. I can't believe how clear they are. I'm definatly not an optics expert but I was comparing them to the glasses that I've been using for a few years now and couldn't tell the difference. I can't wait to see some game through these things. Hope you guys are wrong about the head ache (no offence)