Now, an approx. $50+/- single BA IEM with a neutral/reference tuning, and superb isolation, would be a real gem! Such a product could serve as the best affordable stage monitor. It would definitely have to be <$100, o/w it would be going up against Etymotic.
Edit: actually, I don’t how good the isolation of the SSR can be. Maybe it can already serve in this capacity.
Some of the Audiosense budget models which are pure BA setups cost $50ish and are rather neutralish with good isolation and good fit. TBH I've not found excellent isolation in most single DD sets (as they are generally vented) compared to unvented BA types.
I doubt SSR will isolate as great as the etys and multi BA types, but SSR looks like it can be a possible ety killer with a diffuse field tuning but not in the deep insertion style of the etys, and at an affordable $40 pricing. Can't wait for reviews on SSR!