Not really suitable for use on the lap.
the feedback would twist it all over the place, it really needs to clamped down.
It really isnt necessary to build anything complicated or expensive.
I currently have it on a makeshift unit constructed simply from pieces of chip board and simply pull up a dining chair with some cushions on for comfort.
Simply cut 2 sides to a height to mount the wheel at a suitable height when sitting, then cut a piece wide enough to fit your legs in between to clamp the wheel to, use brackets to fix the top to the two sides, then simply get two smaller strips of wood the same width of the top and use brackets to fix them to the back. one a quater of the way up the 2nd three quarters of the way up, this is to give stability when the wheel shakes vibrates.
the size of the unit is relatively small and can easily be moved about when not in use.
the whole thing cost me £10 bargain.
And does perfectly well till Gt4 arrives and i get myself a full race seat set up.