I have a Horn Cabinet. I don't like it particularly, but I got it for a song, with a free machine. I bought it because I remember my Godmother having the same model, and at the time I thought it was a neat solution.
It now houses my 611g, and as a flatbed it is nice to sew on, but, the storage door is a nuisance, and not practical, and it's a pain to pass the leads through, if, like me, you keep it against a wall.
I think the alternatives all sound much more useful, and flexible, and look forward to seeing your solutions.
Jessie