I've just discovered a great gel pen called 'Zebra' where you can get a pack of two retractable gel Pens for a pound in poundland. They write like a dream and has a medium tip which is more durable than a fine tip. These are cheap enough to buy as disposables, but apparently you can also refill them. If you find them, try them. Gel pens are much better than ballpoints and now are also more affordable, and work well in all temperatures.