Darryl, I'm fortunate to have the Vipers & the Pentax ED. And while the Viper's are indeed excellent the ED's are superior! Their color, contrast as well as resolution top the Viper's. In regards to CA the Pentax are better and I feel lense flare was less evident on the Pentax. Now price goes to the Viper's. But, what you get in the ED's for price is also excellent in comparison to the top 3-4 binocular brands. Especialy since Pentax price has leveled off. Both should be considered best buy's in there price category's. I don't think any body could go wrong with purchasing either, though I think one needs to put every thing in perspective when making direct comparison's. Being able to compare directly in the field in the real world as I have been able to do brings out +'s & -'s of each. I sold my Leupold 8x42 Pinnacles and replaced them with the 8x42 Viper's and I cannot be happier but, that being said my favorite bino that I grab more often than not are the Pentax DCF ED 10x43. Every-body has their own opinion's, I'am glad you are so stoked about you're Viper's and I indeed hope you get great year's of enjoyment using them. Stereo...