You drive up, sit in your car for 40 minutes and drive off - there's no faff (unless some overzealous UK border guard asks a bunch of questions on a British passport like how long I'm staying, when I'm going back, do I have accommodation, etc) - if you're early or late they just put you on another train, you can easily take pets (for us two dogs).
I'm glad it's there, keeping some kind of physical connection to Europe.