The short version
Same water-cooling mechanism, different tiers. Dock Pro adds dual-zone, scheduling and a higher-capacity chiller. Cube delivers core single-zone water cooling at half the price.
When Dock Pro is the right pick
If you sleep with a partner who needs a different temperature, or you want app-based climate scheduling, or you live in a hot/humid climate that pushes a smaller chiller — Dock Pro is the right shape.
When Cube is the right pick
If you sleep alone, you want set-and-forget water cooling, and your bedroom climate is not extreme — Cube is the right shape. Same Sleepme architecture, half the price.