Metal can impart a bitterness that isn't nice, coffee itself SHOULD be bitter. Caffeine itself is bitter. Whats a/the keurig?
I did have a french press and I need to get another after the glass broke years ago. The filter I recycled for other uses but the press, before breaking, does make wonderful coffee.
Taking as axiomatic of course, that one HAS some wonderful coffee to put into it. Put cheap garbage in, and thats what one gets out again obviously, and if someone is prepared to buy utter garbage to begin with then they might as well save the money and buy nescafe or some such trash. Or ask CBC to teabag them.
As for half and half then, gah, thats fucking gash! your polluting the environment with filth, not making coffee or tea, if cow products aren't thoroughly excluded from being present. Eww, thats just nasty. I can't stand milk in tea or coffee. My coffee, although I drink less of it than I do tea (go figure, I'm english, and proud of it
:P) I take black, preferably rich, strong, aromatic bitter-sweet espresso, or mmmmmmhhhhmmm turkish coffee is manna from heaven. For my tea, black of course, and if sweetened at all, although I do usually like at least a spoonful of honey dribbled in. If its the right kind of tea, that would benefit from the flavour, then my favourite additive/alterant for it, is chopped freshly picked lemon balm (Melissa officianalis) from the garden, bashed up a bit to release all the juices and scents and flavours, then left to infuse with the tea, then hoiked out before drinking it, because otherwise it would just be a tea soaked gobfull of leaves and twigs and little white flowers.
Its worth a try if you like tea, just let the chopped balm (about as much as will comfortably fit in the cup, and within one clenched hand, nothing more to it really), meant to be very healthy stuff too for the brain, meant to support memory via IIRC, nicotinic acetylcholine receptors, as well as a gentle calming effect (this is nothing to worry about, one can even give babies Melissa water, for their griping and skriking, as well as to ease intestinal gas, indigestion for them, its so benign a plant about the only way I can think of to do harm with it, would be to choke to death on the plant matter itself if forced down one's throat, or bash someone over the noggin with a heavy plant pot full of it, and soil and rocks etc.).
The soothing antianxiogenic, calming action is due to compounds having the effect of inhibiting GABA-transaminase, a catabolic enzyme that plays the role of breaking down the main CNS inhibitory neurotransmitter, GABA. Makes a lovely enough tea actually on its own, without any Camellia sinensis at all, just a drop of honey to taste, maybe a squirt of lemon or lime juice if that appeals.
The french press does come highly recommended. Been meaning to buy another one myself. It takes ages and requires setting up loads of equipment to make it, for me now. Enough to make me seldom bother.