I own two of them - 10x42 and 8x56 both the rangefinding HD-B. Both of mine are first editions and I don’t think I’d pay extra for the ability to range products at longer distances. Can’t really see practical benefits. As for the B vs R. I reckon B are worth it. The ballistic calculator uses pressure, temperature and angle as well as rangefinder to calculate the holdover. In addition to being able to use SD cards with your own data they have a number of built in ballistic curves. They give you the distance reading followed by holdover or click adjustment however you prefer. I bought the first pair in Oz where I had to spot game over longer distances, then moved to Europe and as soon as I heard they released an 8x56 version decided to get it as well. I do a fair bit of night boar hunting and extra brightness and wider field of view are handy and do make a difference. Only problem is you can often see game clearly through the binos but not the scope and I use quality scopes, these binos are super bright. Rangefinding and ballistics work well especially if you put in your ballistic data. Picture quality and brightness are fantastic on both. The front lens covers are super flimsy and easy to loose, particularly on 10x42 version - they belong on a $10 product they're that bad! The ones on 8x56 are an improvement but still crap. I dropped one of my binos from a high seat and damaged an eye cup, they were still completely usable but the cracked eye cup was loose and irritating. I've ordered a replacement from an authorised dealer in Warsaw, Poland (5 hour drive from Berlin) and it took about a month to get it in. Cost was about $30 and I replaced it myself - I have two left hands, anyone can do it, takes 15 seconds no tools. If you're not hunting at night I'd go with the 42mm version to save on size and weight, you'll appreciate it walking all day - 10x for open terrain and 8x for forests and similar areas, they are still bright and are perfectly fine for twilight. At night every extra bit of vision matters and 56mm versions have a definite edge there. If you buy them it's worth spending few minutes adjusting the oculars to your vision, both sides are independently adjustable. Once you've adjusted them remember the settings, you can't lock it and every time my friends look through them they just have to fiddle with it.