For the first 50, your lines are very clean overall. I noticed minimal arcing or wobbling throughout the set. Your convergences also show decent accuracy, though I did see some lines pair off and converge towards two vanishing points, like box 7's yellow lines, box 20's pink lines, and box 43's purple lines.

For the next 50, your lines remain clean throughout the set. As before, I noticed very little arcing or wobbling. Your convergences also show improvement, though I did see a few more instances of lines pairing off, like box 54's purlpe lines, box 70's blue lines, and box 96's pink lines.

For the last 150, your lines remain clean and even throughout the rest of the challenge, demonstrating very good technique and consistency. Your convergences continue to improve, though there are still instances of lines pairing off, like box 128's pink lines, box 174's green lines, and box 230's orange 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 66 and box 94 are missing some line extensions. It's not a major issue since it didn't happen often, but I want to point it out for future reference.

Also, while it wasn't common I did see a few pages like here where you only drew a few boxes. There was also the odd page, like this one, with extra boxes. As noted in the instructions here, we want 5 or 6 boxes per page, to make the best use of space without making boxes too small.

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