Yes compact case keyboards have shipped out as part of the 300+ Brand New Model F Keyboards that have gone out so far. As I’ve noted on the forums, the sound of the Model F has more to do with the tensioning between the top and bottom inner assembly plates than it does the material of the case.
However if you are unsure of which case to go for, I recommend the original style die cast zinc. These are heavier than the compact aluminum cases and have the original style powdercoated finish. There’s also room inside for a solenoid driver and custom made solenoid (there are solenoid drivers available in the store now, and I am ordering the custom made solenoids in the coming weeks).
To quote my Deskthority post from December 2019:
Each new Model F keyboard will sound different, and they will also likely sound different when they are as old as the original Model F‘s.
But yes I do hope people experiment with their new Model F‘s and share their mods to tune the sound of their new Model F keyboards to their preferences, even if the factory sound is not 100% to your liking. I have found that using a vice and taking a rubber mallet to adjust the bend/radius of the top inner assembly has a noticeable effect on the clickiness and reverberation of keypresses. I successfully improved some of my original F107s with this method a few years ago.
I have done some brief experimenting with foam (putting foam inside the metal space bar tabs as a cushion and to increase tightness of the space bar, doing the same with different types of tape like electrical and plain clear tape, etc.).
Also I think some people will even remove the inner foam entirely in order to maximize the clickiness and reverberant sounds of the Model F. (This may have drawbacks in terms of more wobbly keys and the possibility of dust interfering with the capacitive sensing). Currently the foam is brand new and undegraded, so it may muffle the sound more than the deteriorating inner foam of an original Model F.
Allow me to quote the project home page for a more general note on Model F sounds: “I have many original Model F keyboards in my collection and each one sounds different. No two sound the same or feel the same when typing! This means that your Brand New Model F Keyboard will likely not sound or feel like your 30 year old Model F or Model M keyboard due to their loosened springs, deteriorating foam, different alloys of metal, etc. New or little-used Model M and Model F springs and keys tend to require a little break in to loosen up the springs and keys. Not all keys will sound perfect or all the same with buckling spring keyboards – some may sound funny but they usually keep on working.”
In summary: if you want to, the keyboard will be yours to experiment with and adjust both on the software and on the hardware side to get the best configuration and sound.