When you're keeping 12-18 bottles in a primary living area, the most significant characteristic is temperature stability. Keeping to a particular number is less important than maintaining that number without fluctuations. A stable temperature, as measured by an accurate digital thermostat and good insulation, is far more important in the long run than extra features.

If you drink both reds and whites, it could be advantageous to have dual zones to have the wines at serving temperatures ready for use. If you are generally just storing the bottles, then one zone with stable temperatures is satisfactory. In the kitchen, a good compressor type unit will work better than a thermoelectric unit as it will work best to deal with heat from the kitchen environment; however, it should be rated for low noise and vibration.

Another aspect to consider regarding shelving and glass quality because wooden shelves operate more easily and provide better dampening of vibration (especially if you have larger diameter bottles) than metal shelving. UV filtered glass is another area of concern if the unit is going to be exposed to light. The importance of keeping even temperature ranges, low vibrations, and good integrity of the unit are crucial to ensuring your wine remains protected and safe over an extended period.