That would certainly be a determining factor. This one is set up for Service Rifle competitions.
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I bought that scope on Art's Recommendation. It'd be nice if it dropped down to 1x ,but unless you're blasting at lots of stuff at throwing distance as fast as you can, it's not an issue. As far as bringing a rifle up onto a target quickly, no problem at all. Definitely a keeper. I put it on my 'charter boat' gun for 3 hour tours. I don't have a boat yet, though I did have a boating accident....
If you wanted the lowest mount without any potential extraction impediments, as well as minimal weight, I think it would be a Bula XM-21. I don't have an ARMS-18 for comparison, but visually they look pretty close, and when you ditch the rear peep sight altogether, you save that... I don't have hard data on this in terms of weight differences of total hardware, or exact height comparisons, just intuitive speculation.
But to get a 50mm objective bell to clear on my XM-21, I needed to get medium rings to bump it up, as low actually hit the handguard. The center of that 30mm scope is still 1/4" lower than the center of a 1" tube with low rings on my Fulton 'Brookfield Type' scope. Without the front objective, you could drop it that much further with actual low rings.
Interestingly, ARMS low rings aren't as low as Warne or EGW low rings.