Should I use a V60 or a flat-bottom dripper?

The difference is bed shape and flow restriction. A conical V60 has one large hole and steep walls, so the coffee bed is deep in the middle and shallow at the edges, and water flows out fast unless the grind slows it. That means your pour technique controls contact time, which is powerful if you have the skill and unforgiving if you do not.

A flat-bottom brewer holds a shallow, even bed and restricts flow with several small holes. Because the depth is uniform, water passes through a similar amount of coffee everywhere, so extraction is more even by geometry rather than by technique. The flow restriction also means the brewer, rather than your pouring, is setting much of the contact time.

In the cup, the usual characterization holds up: the V60 leans toward separation and a lighter body, the flat-bottom toward balance, sweetness and a slightly heavier, rounder texture. Neither is better. If you have ever chased a specific floral note in an Ethiopian, the V60 is the tool that shows it most clearly. If you make coffee for a household and want the same result every time, the flat-bottom is the tool that gets there with less fuss.

Practical selection notes. Flat-bottom brewers generally want a grind a step or two coarser than the same coffee in a V60, because of the flow restriction. Filter papers are not interchangeable between the two shapes and using the wrong one causes leaks around the edge or a stalled bed. And material matters more than it sounds: ceramic and glass steal heat unless preheated, plastic holds temperature best, metal drips fastest and lets more oils through.

If you own neither and want a recommendation: buy the flat-bottom first if consistency matters more to you than ceiling, and the V60 first if you enjoy technique and want the more expressive brewer. Both are cheap enough that owning the pair is a reasonable end state, and the same grinder and kettle serve both.