I know I am out of date with my post but maybe it will help anyone else.
I am not a pianist with a classic musical education but a keyboard player with some time spent on classic pianos.
During last several years I played many digital pianos, master keyboards and classic pianos.
What I really recommend for studio work is
Oberheim MC2000 or 3000. It is an ideal keyboard for those who are not a pianists because it has very light hammer action that is easily playable. People used to play digi pianos can have a problem with it since action of piano is much heavier but Oberheim is not for training of the technique but for long hours work in studio.
The keyboard is light and fast so it can be succesfully used for organs/strings/synths but it has also hammer action so it is great for piano sounds.
Next it has a huuuuuge amount of controllers (wheels, connectors, sliders, etc.) and the instruments body is made of steel so it is very solid.
I did not find any other product comparable to this unit.
Doepfer masters are also built like a tank but their keyboard is more close to semiweighted keyboards than hammer ones. Therefore it is good for organs but less suitable for pianos.
CME UF80 has a decent keyboard action, that is somehow similar to Oberheim but masters from this company are quite known by a many problems - both mechanical and electrical.
Digi pianos are not so suitable for work in studio because they do not have controllers and the keyboard action is too heavy for long work.
M-Audio products I take like a funny toy, not for real work. Played them several times and the action on both semiweighted and hammer keyboard is in my opinion terrible.
As for Fatars I made a bad experience with
TMK88 where black keys played louder than white ones and also action generally was poor. After some time I sold it. Maybe higher models are usuable but I read many bad reviews on them.
To make it short I do not know any other so universal product comparable to Oberheim.
There is only one problem with Oberheim.
Their production was stopped and you can buy only last stocked units.
Several last units are sold at
www.musicstore.de who is an official representaive of Oberheim for Europe and maybe on some other places.
This is a photo of mine MC2000: