I bought the model in size MT4. The bearings on it are very smooth and it turns very easily on what I got. Other reviews that have mentioned bad bearings say they are for the MT3 model, so maybe the MT4 is better, or maybe I just got lucky with a good bearing. It's definitely very good for the price. MT4 Dimensions: 2.125" nose so a 2.25" bore/bore stock would be the minimum size you would use for a 0.5" diameter at most of the head. Standard morse taper 4 shank.