It seems like a good solution, at least for now.. and maybe a bit better (or less ghetto?) than tape and a sponge... or am I wrong? I was looking at Karsten cheek rests, but im not sure how the whole thing works.
If duct tape and a sponge is a little too Sanford & Son for you, a chunk of black pipe insulation (the semi-rigid kind with a slit down the length) is a cheap alternative.
P.S. the guys who have modified their equipment themselves with less-than-store-bought materials are my heroes. Up here, we're all cheap and you see some really interesting contraptions on the line.