For their purpose, I think the Ashley big dots are wonderful.
Of course, the devil is in the details. Their purpose is to give you an easily acquired sight picture that you can refine 'a little' if you have the opportunity. They are not general purpose sights, and they are not match sights. They are for fast social distance engagements.
My new favorite sights are the Sig X-Ray 3. Slightly dim rears and a large, bold green front work nicely for quick front sight acquisition. They win over big-dots for general purpose use by allowing a conventional sight picture for slower, more accurate work. I see they come in square and U rear slot versions, but I have not had any hands-on time with the curved version.
The F8 you chose was one of the options I was looking at to replace a broken big-dot on an M&Pc. It might have been what I went for if they hadn't sent me a replacement.