I would love a floor like that, but I have a large crack in the middle of my floor that I assume would not be great to install these over top of…or are they ok for that?
Concrete cracks.
This is not a problem which cannot be overcome.
The crack in the middle of your floor is probably an original shrinkage crack that is no longer moving.
There are all sorts of fancy gauges to verify this, or you could use two painters stir sticks, a bit of tape, and a marker.
Fasten the first on one side of the crack (only) - tape will suffice.
Fasten the second on the opposite side (only).
Ensure the sticks are pushed against each other.
Draw a straight line across the two stir sticks.
If there is any horizontal movement, your line will separate.
This will take a significant temperature change to show up, so make yourself comfortable.
Assuming there is no continued movement, grind a 1/4" x 1/4" key over the crack, then fill with epoxy (you can use a grout if the crack is very large).
Polish the uneven lines with a cup-stone grinder, and you should be good to install your flooring.
If, however, you find the crack is moving substantially (>1/8"), you would have to allow an expansion cut in the flooring directly above the crack.
The tiling companies have movement strips, just for this very purpose.
Get the floor you want - the crack is manageable.