I find 4x to be the comprimise between size and usefulness for bins. The bigger and heavier they are the less likely they'll be around your neck! As far as the Monarchs are concerned the 8x are great however to my eyes 10x shows the quality or optical flaws. I suggest going a step or two up when considering 10x's as a rule. You'll find the low light performance better as well as other gains in optical perfromance. You may want to consider in 10x something like: Minox HG's, Vortex Viper or Razors, Zeiss Conquest, Swaro SLC's, etc. However these all run in the 500 - 1000 ish range.One other thing you'll notice with better optics is on a hunt wear you feel like your wearing them, eye strain will be less. Personally that is want led me to breaking out of the mid range bins. I have come to enjoy other nicebenefits with my 10x43 Swarovski EL's.... They are spendy but the way I was ripping through bins, cheaper in the long run. I use them much more then my spotting scope, before my spotting scope was a constant during pre-scouting...they are that good or maybe my spotter is that poor...