I used both but wooden pencils went I shading and going over important details with a sharpened grade 6b wooden. Just to get them crisp dark lines.
It all depends on what your after. How much your willing to spend. And llastily the look. For me. Quick stretching metallic pencils. You dont need to worry to much about the lead. Went the nib snap off or wears off its not that much off a worry. Just annoying. Just make sure you have plenty of lead spares.
The normal pencils tend to go off how cheap you want them. If you go as cheap as you can go they tend to be rubbish. Lead within them fit for the bin.
For me I bought a ten pound set of 12 pencils with sharpener and rubber.that was four years ago and im still using them now. The other thing is the type of sharpener. They can also be a royal nightmare for your pencils