Testimonials section with grid

This one actually went faster than expected. I can't get all the spacing and sizing right because I made it from the jpg file, but I'm quite happy with how it turned out.

I'm not sure about the breakpoint between the mobile and desktop designs --- I just picked it based on resizing the viewport and looking at what looked nice (and what didn't).

I feel that there should be a tablet layout too because both the desktop and the mobile version look awkward in a tablet-sized viewport.

What are the current best practices for breakpoints? How common is it to have a special layout for tablets?