I use aluminum adjusters on my bridge and they work fine. But I notice that the distance of the strings varies, and I feel the diference when playing, with the weather temperature.
What material is less sensitive to temperature: brass, aluminum or ebony?

Its not the adjusters expanding and contracting with temperature fluctuations, but the top and back swelling and shrinking with the changing humidity. The spruce top will take on and lose water quite quickly, making it grow and shrink.

The adjusters are there in part so that you can raise and lower the bridge to compensate for the changes in humidity.

An inexpensive digital hygrometer will let you see the swings in humidity and you'll be able to relate them to how your bass feels. Then you can decide whether you need a dehumidifier or a humidifier, or both!