depends on what your criteria is....there's no way any of those cars will see 30mpg.

my FRS was about 19-20mpg round town and would do 300 miles if you took it easy on the motorway 25mpg - blufin remap, few other mods.

i also have an E39, not an M5 but can vouch for their build quality, my derv only does 25mpg round town so i dread to think what the 4.0 V8 would be like

having never owned or driven an Evo i cant comment, feedback from people i know are they drive and handle superbly, but cost alot in running and fuel....and the interior as said is a bit plastic.