A complete mixture for me. Fabric is 100% metric in my head when I buy it, but I cut it in feet and inches.
In my kitchen I have traditional brass scales with weights - it came with imperial weights years ago, but I now have a set of metric weights as well.
Temperature is always Celsius for me, but my DH always converts to Fahrenheit.
My height and weight are imperial, but I make my GC's clothes according to their metric measurements.
Still tend to think of cheese, meat, veg etc in imperial, but I wonder if this is more because in general we haven't always had to actually ask for 150g, or 2.5k of something - we just pick it up off the shelves in the supermarket.