Actually prefer those that use water and are slow-moving despite a bit of mess, also always paired with a jig that holds the drill in place exactly where you want the hole, like with a hole saw, for example, so you have no mm to play with if it goes wrong, then the slow one is preferable. Then the hole after water drilling is generally neater, high-speed drilling without water tends to fray the edges and chips are more likely to come off.
