I drink about 3 cups a day on a college day - 4 if I brave the dish water that comes out of the vending machine in the cafeteria, and approximately 5 cups when I'm at home all day. If I go down to visit my folks in Yorkshire it can be almost double that - the kettle is rarely off the boil there!
Being a poor student (and a tight git to boot), I use what ever brand tea bags are on offer in store and failing that, stores own brand (Sainsbury's Red Label are quite good for the money), but never ever any of the basic or value ranges- I may be cheap, but I still have some standards!.
Always use tea bags, never loose (unless it's a speciality tea), and rarely make it in a teapot, no matter how many people I'm making it for.
One tea bag per mug, add water straight off the boil, leave for a minute, remove tea bag (WITHOUT stirring or squeezing the bag), add a dash of milk - not too much, stir, drink and enjoy!