I'm buying my first coffee press but...?!
Oh I love french press coffee! The larger 32oz would probably serve you better then the smaller, unless you want to cut your coffee consumption a little otherwise you'll have enough to share with a friend :). Bodum makes some nice models. You can fill them with less coffee and water but they are designed to make a perfect cup of coffee when you fill them as instructed. Be sure to wait the full 4 minutes before you press, so good! I just broke my 12oz and haven't replaced it yet but now I will, thanks for the reminder!
Because the French press has you "pressing" the coffee grounds through the hot water, you are going to end up with a bit less liquid in any size that you buy. I would reccomend the 16 oz model. It's a bit smaller than what you drink, but getting the really big one and making to much wouldn't work out too well I think. French pressed coffee is not that great reheated and that's probably what you would have to do with more than enough. Just make another 16 oz when you are done with the first. Tastes great and really doesn't take that long.
You could also make your coffee pretty strong in the french press, then add hot water to your cup once you pour it to make your usual 20 oz.
YES THAT OK I DON'T LIKE COFFEE, BUT I'LL TILL YOU GO FOR IT.
haha. just get a small size and try it out....