First impression of the Staedtler Mars Professional Technical drawing pen set

Ooops did it again! Got a bunch of drawing and drafting supplies earlier today. Always wanted to try one of these neatly packaged Staedtler Mars Professional Technical drawing pen sets. Finally was lucky enough to find one that was not overpriced. Keep your eyes open for them at office supplies stores blow out clearance sales.
Pretty sharp looking pen, and a lot lighter than one might think. Its ergonomic grip features an integrated roll-stop boxy protrusion on the side that prevents the pen from rolling off the drawing table. It draws smoothly at different angles unlike traditional technical pens. Its 0.25 mm felt nib tip encased in a metal sleeve feels quite solid, but it is far more pleasant to use than the scratchier Koh-I-Noor Rapido Sketch 0.25 mm pen. Very good first impression. Plus the test doodles dried quickly and did not smear when colored with the water-based Pitt artist pens.
These pictured Staedtler product lines perform pretty similarly since they are both new. Given the significant difference in their suggested retail prices, I'd imagine that the Mars Professional Technical drawing pen must be sturdier than the lower priced Pigment liner pen and should last longer. Further testing and time shall reveal the truth.