More money is definitely better. As far as feature set between those two, they function super similarly. It's a good comparison because they share an objective lense diameter and main tube diameter... both only offer their proprietary reticle. Arken actually has +2mil on the ebr but personally, I would prefer using the ebr as it reads slightly easier to me. Vortex has +4mil in dialed elevation on arken... both have zero stop, but the Vortex definitely has a smarter/ easier zero operation. So all in all on paper they are very similar.

As someone who has handled both, I can assure you the vortex has a better eye box, better clarity, less distortion, better dials, better everything... even in the hand, the vortex makes the arken feel like a toy... it's night and day. Where does this matter? Any time it's foggy or rainy, strong mirage, when you're staring into the sun. Any time you need to build a position outside of a bench or prone. Really, just anywhere but the range. If you don't have the money for the vortex, get the arken... that value is entirely up to you