Do a search and you will find many threads discussing this.The concensus among most people,is that the ziess is clearer and brighter.It also offers constant eye relief unlike leupold.But there will be one individual that will try to convince you that the only scope to even consider is leupold.He will offer fanastic rumours and unproven opinions to try and convince you.He hasn't even owned a ziess scope,or hunted with one.His name begins with E.