Medium diameter and light weight. The spring loaded clip is a bonus at this price point. These two light weight models have good flow and a medium diameter. The differences in the 150 and 200 are mainly cosmetic. Sheaffer has done a good job with their newest line.
Flow is good and the nib puts out a consistent, precise line.
With a medium width and hefty weight, these pens are similar to the Parker Sonnet series. Excellent ink flow with a thin diameter and a very light weight. A very fun pen and highly recommended. With the only solid gold nib on this list, the Vanishing Point writes as well as other pens costing several times its price. It's the only fountain pen with a retractable nib.