I'm a fan of mechanical pencils myself. In school we were issued Pentel P205's and every few years I buy something new to try and always end up returning to my 30 year old P205 pencils.
That's it. It's nice that something so inexpensive can last decades. You can spend a lot more on a mechanical pencil (and I have) but none have won me over.
If someone could marry the eraser of the Pentel with the auto-rotation mechanics Uni Kuru Toga, I'd have a dream pencil.
The Kuru Togas are just crazy good and only like $8. The only thing that sucks is that their eraser is super tiny and also structural. It's the only thing keeping the lead in, unlike the Pentels, which house their erasers in a metal sleeve.
I have a Pentel PS315 that's older than I am and it's basically the only pencil I've used for the last fifteen years. The 205 and 207 they still make aren't as good as any of the sliding sleeves from the 1970s or 1980s. The mechanism gets caught sometimes, it's much more difficult to get lead from a quarter push, and the eraser caps slide off easily on the new ones. So I just keep using the PS315.
