Pilot Metropolitan Fountain Pen
Twenty years as the unanimous first recommendation, and it earns it every time. The steel nib is smooth out of the box, the weight feels right in hand, and it accepts Pilot cartridges or a converter for bottled ink. Available in fine and medium nibs — medium is what most people want for everyday writing. Under $25, and it'll last indefinitely if you rinse it occasionally.
Watch out for: The included cartridge is a squeeze-fill that holds very little ink. The CON-70 piston converter (sold separately, ~$8) gives you full-bottle access and is worth adding to your first order.
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