I have a mix of all three in my 20mm early war armies.
Metal kits tend to be fiddly to put together and are pretty heavy.
Plastic kits are also usually fairly fiddly to assemble.
I am a big fan of the resin vehicles from Frontline Wargaming
which mostly just need tracks adding to tanks or wheels to the lorries. They are quick to assemble and paint up very nicely.
I don’t notice the difference between all three types on the table.
Black Hat Miniatures -