best mini fridge reviews no. 4. SPT RF-244SS Compact Refrigerator. There are six different sizes of this SPT model, ranging from 1.6 cubic feet ($120) to 4.4 cubic feet ($210), and the prices don’t necessarily correlate to their sizes – the 3.5 cubic foot unit costs $55 more than the 4.4 cu. ft. model, for some reason.