It looks to me like it would cover up an awful lot of the target.
Be really hard to see your bubble.
In my experience it doesn't cover up any of the target or the bubble. Mainly because it is too close to the eye to have any definition. You still get a basically round aperture...it just adds a little fuzziness to the sight picture. Like most things in archery lately this is not a new concept. People have tried this many different times over the years.
Ask yourself this question next time you shoot your bow - How far does my peep need to be from my eye to see any definition? The next question to ask yourself is - Once I do get definition of my peep aperture how clear is my view of the target? Each person depending on eye sight and youth will experience things different when asking these questions. But, I think you will agree after your answers that designing a feature that takes focus off of pins and target isn't necessarily a benefit. Peep sights are meant to be looked through, not at.
Our subconscious mind centers things in a circle naturally. So what is the purpose of designing a feature that requires us to consciously do the same thing? And then does it with a lack of definition and disrupts clarity? Obviously my company is a competitor so most, I assume, will assume my views are slanted. But in my experience with all the other similar designs, some with lenses some without, it has never been a benefit I wanted to add to our product line.