It's a choice that will shortly be taken away from me - on international travel (which is mostly what I do) at least as I drop from E50 to E35k. I'll miss that nightcap in YYT MLL before boarding AC822 - not because the lounge is particularly nice (its rather tired) but because nothing else is open in the airport at that time other than the landside Timmies. This will change next year when the terminal extension opens but I digress...

At LHR I'll miss the Lufthansa lounge which is where I go in preference to the MLL. It's bigger, nicer and has better food IMHO. No biggie though as T2 is ratehr nice & The Gorgeous Kitchen restaurant is a perfectly pleasant place to grab a leisurely breakfast before boarding AC823. Even sitting at the gate wouldn't be too bad.

On my rare trips through YYZ, if it's beer o'clock I'll likely seek out the Mill St Brew pub. I would agree that as some airports improve the quality of their food and drink outlets, the appeal of a lounge, certainly a MLL, diminishes. Particularly for the business traveller that can expense what they need during a layover!