I generally prefer to pay cash if at all possible as I can just put it on the table (with a small tip) then leave when I want.

I do find it comfortable, when paying with card, if they have a portable terminal that they take to the table. However I also don't mind walking to the cashier if necessary.

In holland it's maybe 50/50 whether they have a portable terminal or not, maybe a bit more common that you have to walk to the cashier.

I would be very uncomfortable if my card were taken out of my sight. I would always walk with them to see how they process the payment. Cards being taken out of my sight never happened to me then again I have never been to the US. Even in Brazil they don't do that though (probably quite logical, no brazilian would trust people taking away their cards, haha).