what is the difference?
If you search around on this forum - you will find comments to the effect that the Extreme's have a bit better optics, water proof and better eyerelief ( comfort and using glasses) over the Aculon / Action ( non Extreme).
I suggest the Action Extreme or Bushnell Legacy. For a bit more money you get a lot more value. They are lifetime binoculars - and if your eyesight changes and you need to view with glasses in years to come... piece of cake.
I don't have much Roof prism experience and many say they are just as good, others say there is some 'spikeyness' to the stars from Roofs. However that being said - i just recommended to a friend to buy a Nikon 7S 8x42 ( on sale ) for ( beginner) star gazing - since the person has a small build and i figured 8x is easy on the shakes, and a roof is compact and lighter to carry and store. They are borrowing my 10x50 now to get a feel for the difference in view and weight. This could be pertinent to you as well.
Barring Image stabilized - if i could only have ONE - it would be a 12x50. I like my pentax a lot for the money. And the Action Extreme 12x50 are Legendary on this forum.
BUT as already stated - 10x50 also is a bit wider and brighter and easier to use. 10x50 is a standard universal all round general purpose no nonsense do everything jack of all trades ( yes... master of none) configuration. 12x gets a bit more detail... but you have to have practice steadying it.
Edited by Nate1701, 23 October 2020 - 10:01 PM.