My store bought Lithops (bought in early 2016) are still hanging in there after another winter on my balcony. I watered them last week and they plumped up nicely. I may be able to water them once more in spring before the warm weather sets in. If not, they will survive just fine for the next 6 months without water.
I really love the bright, almost white Lithops, even though they’re slightly etiolated from the lack of sun. When the sun shines behind them, the top of the plant looks almost see through.