For the first 50, your lines are clean overall, though there was some wobbling throughout the set. Your convergences also show good accuracy, though I did see some lines pair off and converge towards two vanishing points, like box 6's red lines, box 26's blue lines, and box 48's purple lines.

For the next 50, your lines show improvement. While some wobbling is still present, most instances are not very dramatic. Your convergences also show improvement in accuracy, though there are a few more instances of lines pairing off, like box 53's red lines, box 79's blue lines, and box 100's blue lines.

For the last 150, your lines continue to improve, with very little wobbling by the end of the set, showing very good technique and consistency. Your convergences also continue to improve, though there are still instances of lines pairing off, like in box 117's red lines, box 175's blue lines, and box 238's red lines. In these boxes, the inner lines (green and orange in this diagram) diverge instead of converging at the vanishing point. Keeping in mind the angles of neighboring lines can help when planning the box's construction.

As an aside, box 3 si missing some line extensions. Also, box 62 and boxes 56-58 have some lines extended in the wrong direction.

All said, you did very well. I'm going to mark this challenge as complete.