I'm a piano student that travels regularly. I have a nice upright at home, and I miss the feeling of a weighted keyboard when practicing away from it.

I have owned a Yamaha NP-12 for a short time, but I did not like the feel of its semi-weighted keyboard.
A few months ago I bought a Yamaha P-121 and the feel of the GHS keyboard is very nice. However, the keyboard is too long (about 4" too long) and I cannot easily transport it by car, together with family and luggage.

So I ended up buying a used basic semi-weighted 49-keys MIDI controller to connect to my iPad for travel practice. The feel is nothing special, but it was cheap and as I read even more expensive keyboards with semi-weighted keys aren't that much closer to the feel of a real piano.

I'm in the market for any keyboard (stage piano or controller) that is less than 1m (39.5") long and has fully weighted keys. So 64 full size keys and small "bezels" is the maximum that fits my car. 73 keys are too wide, without even considering any bezels.Unfortunately, it seems that there is no product with such specs on the market right now, so I might have to consider a keyboard with semi-weighted keys that come close to the feel of a real piano.

Yamaha P-121 (73 keys) and Roland RD-64 (64 keys, discontinued) are both about 44" long.

The Studiologic SL-73 MIDI controller has the nice and light Fatar TP/100LR action, but it's 1.5" too long, sadly.

Back in 2004-2005, Studiologic released the VMK-149 and VMK-161 MIDI controllers with Fatar TP/40 hammer action, but they were since both discontinued.

I hope that one day Studiologic will make a 61-key version of the SL-73, or Yamaha a 61-key version of the P-121.
Or, that Roland or Yamaha will upgrade their 61-keys Go:Piano or Piaggero NP-12 with a hammer action keyboard.
Not holding my breath, though: I just mailed Yamaha and they told me that no such product is in the pipeline.
I mailed Fatar and got no response.

Every now and then there have been attempts at making and selling a modular or foldable piano (see "VAX77", "KOMBOS", "piano de voyage" in this thread), but the prices were usually very high or the performance below expectations. The travel piano should not cost more than upgrading my car.

I'm also considering DIY projects, but since I'm not particularly skilled with electronics, I suppose the safest choice would be getting a used RD-64 and re-package it so that the buttons are behind the keyboard instead of at the left.

Thanks in advance for any alternative suggestions, including solid (pun intended) semi-weighted keyboards.