Those guns and turrets are good for a light (anti-air) or medium ship artillery, main caliber turrets shouldn't be so flat at the sides, they are more roundish. Smaller guns also probably don't need the bores modeled (of course I don't know how big they are going to be ingame), that would save polycount considerably. Otherwise good, model a ship with those and show it there
Not bad, just needs to be more interesting. Try pressing every button on ur keyboard and clicking the mouse around in ur modeling program to see if you can make some more abnomalities.
It's fine for a starter. There are a couple of errors like one or two unecessary bevels and some other stuff. Keep in mind that you don't have to model small details like the insides of a barrel, especially small barrels.
that looks like Sketchup, so good luck getting that into wings to UV map it without having Sketchup Pro
anyway, they look good as a start, just more detail/thought needs to be added to make them more interesting. Mabye you could model a ship or something then add these onto it ?