I love my mechanical pencil. I have almost entirely converted to them. It might be that I am usually drawing on the go, so I do not have time or room to use sharpener every so often but I think it also suits people who, like myself, are large-format shy and prefer small sketches to have everything under control. This allows me to put in plenty of detail into a little thumbnail.
Don’t get me wrong, the richness and softness of a regular 2B lead is great but to me, as far as sketching while travelling combined with an M size sketchbook is concerned, mechanical pencils are a way to go. And you can get them as cheap as chips;)) I got a whole set (three pencils, tube of spare leads, and – this is great: a whole set of replacement erasers!) for something around £1.50 at Asda. Cheee-heeeeeeaaap!
This girl drawing shows clearly that I have been to eraser-happy as well as if you do not have an idea of how a Victorian type of dress should look like, you’re better off sticking to trousers or leggings until you get same references. Whatever. A quick check on what to improve on is priceless.