I have planted out several lawns with either Carex pansa or Carex tumilicola, and love the results and the reduced watering needs as well as the easier care. Both types of Carex also do quite abit better in winter shade than typical Fescue lawns, and paradoxically can take both too wet in winter soils with poor drainage and no sun and baking hot in summer with only once a month soakings and still look vividly green.
The disadvantages to planting them is that they can't easily be planted from sod or seed, so it is expensive to plant them out from plugs, or dividing 4 inch containers to extend the plantings. I have planted both types this way with approximately 3 inch on center spacing, and it can take a good 6 months for Carex pansa to fill in, and slightly less for Carex tumilicola. C. tumulicola is also easier to plant from seed, as it forms seed readily and is easy to germinate. Carex pansa on the other hand is shy to set seed, but does form runners which give a thicker turf over time. Initially either Carex will look like a rice paddy at first, and will require weeding to keep weeds out, which is more of a problem in exposed areas than a contained back yard with no weeds.
I have two more Carex lawns I will be installing later this summer; one new and one to replace an existing lawn. For both this time around, I have collected C. tumilicola seed now, for sowing out into flats for later transplanting. Alot more work than sodding a lawn, but I will never have to resod either in spring to replace the worn out thin sod which was too shaded in winter, and will not have to worry about water rationing meaning a dead lawn, as Carex tumilicola can easily go 2 months once established without any water in coastal northern California conditions.
I would probably go with Carex pansa if it were more readily available in large quantities, as it is a dwarfer growing Carex that also fills in as a solid turf better than C. tumulicola, but both look great if regularly mowed at least once every 3 to 4 weeks if you like a more manicured look.
Q