Seed Trays

Only thing with your very posh none flimsy ones. Because you don’t have a lot of flex in them you will at times need to have a blunt stick/pencil/pen whatever that fits in the drainage hole to push the plugs out.

One of the nice things about the Charles Dowding ones is that they have a drainage hole that's big enough for a finger so you don't need anything extra to pop seedlings out.

They did do a tray with dowels on it to match the holes - so you could pop them all out at once - that was super expensive. 
I do find my fingers get sore from poking my fingers in the modules, especially when they are a bit split and chipped.