The Caledonian Sleeper is quite good, and has a great restaurant car, but it's generally considerably more expensive than flying unless you book very far in adv

The Caledonian Sleeper is quite good, and has a great restaurant car, but it's generally considerably more expensive than flying unless you book very far in advance, and they do some shunting of carriages at one of the stops during the night that generally interrupts your sleep. It's still a good choice between those two cities, especially if you can replace a hotel night with the train, or can book very far in advance.