Like all other Lamy inks, this one is well-behaved and predictable. I haven't had any issues with show-through, bleeding, feathering, or skipping. It's a balanced ink when it comes to lubrication and flow, and it suits any nib with similar results due to the dark saturation. As someone who enjoys lighter inks that shade profusely, Petrol is a bit out of my comfort zone...but in a very good way.
Dry time for Petrol can be a bit long. I've measured anywhere from 15 to 35 seconds using a fine nib. Results aren't much better in a smaller nib, and they're understandably worse in larger, wetter nibs. If quick-drying inks are your thing, this one won't hit the spot.
Like I mentioned a bit earlier, there's not much shading with this ink when writing. The only time I've noticed shading is when doing swabs. Even then, it's fairly mild. The surprise feature, however, is the sheen that pops off the page. It's really easy to see the red sheen when there's indirect light on the paper. Sheen always fascinates me because it makes the ink appear wet and also gives the illusion of a different color in the right light. It's a fun effect, and Petrol has gobs of it.