Good morning
If price is no issue get the Leupold. You will not regret that... But side by side I think you would be hard pressed to visually see any difference.
The entranace ocular is what will make all the difference at higher power setting. Remember the #3. Devide the occular diameter by the power setting... (40mm / 12x ) If that result still adds up to 3+ you are going to have good deffinition with that power setting. But lets say you have that 40mm set at 15 power then 40mm / 15x = 2.6. Now you may begin to see less.. maybe a shade blurry. Go to 18x and you have 40mm / 18 = 2.2. You will see a difference. This is just a guideline with optics.. but if lenses are well made than this factor does apply.
Mike in Peru