There are lot of pencil brands in the market. While buying the pencil lot of things have to be taken into consideration.
1) Consistency in the values.
2) Graphite quality. (Allows to sharpen it to a point)
3) Erasing ability with kneaded as well as thin eraser.
4) Wood quality.
By considering all the above points I prefer to use these three pencils:
1) Caran d’Ache (P) Grafwood :- These are very smooth & consistent in values. I loved these pencils for their smoothness in application. Any kind of erasing is quite acceptable in all grades. Wood quality is excellent. But the only thing is that these pencils are somewhat costlier than other brands.
2) Staedtler Mars Lumograph 100 :- These are my favourite pencils as per the ability to sharpen its lead to utmost point is amazing. It is the most reliable pencils in case of consistency & using a sharpener. Its 8B is an amazing combination of graphite & charcoal. It gives a dark value without glazing or glare on the surface where most of the artists try to avoid glare on their graphite drawing. Its ability to make a sharp point is amazing and consistent.
Staedtler 8B pencil Recommended! BUY HERE! https://amzn.to/2q1Z7xU
Also, COnte e paris 3b is also recommended for portrait drawing
3) The Blick (R) Studio:- These pencils also are a good choice if we consider consistency in values & graphite quality. One advantage of these pencils is they are quite cheaper than the other two brands.
For extreme dark shades I use staedtler 8B, Generals carbon sketch & Conte a’Paris company’s Pierre noire 3B as per the volume & darkness needed in the drawing. Pierre noire 3B are very smooth oil based charcoal pencils. You will love it and one of the advantages of this pencils is it does not spread over the paper like loose charcoal pencil.