Pentax AD 8x25 WP vs Vortex Diamondback HD

The Leica are priced a 3 to 4 times that of the Pentax 8x25; the only attribute worthy of the Leica is its more compact size but for the rest you are paying for the "name". Incidentally, as a practicing astronomer I have wide experience of optical equipment owning instruments by Carl Zeiss et al. Note added Aug. 31

I would think that as the price goes up the possibility of getting a bad unit goes down, but the worst (by far) of the units I tried was the Maven B1 10X42, basically a thousand dollar model. I found it frustrating to get a binocular this way without trying it out before buying. But this is the world we live in now, and Amazon's return policy does facilitate the process. I must say I was beginning to get a complex about returning these high price items though