Who buys and uses socket rails anymore anyway? Most guys I see are using hansen trays or those twist plastic rails or mechanics time saver magnetic plastic holders.
can you keep the Hansen trays sideways in your box and still holding the sockets? no.
do Hansen trays come in short or deep sockets only? no, both short and deep sockets in one unit.
do Hansen trays standup to heat? no, they are plastic.
the list goes on.
for me, it's more of space issue. I don't have a giant tool box, all my drawers are filled even double stacked. I have 8 Hansen trays and they took a lot of my drawer space. I put some socket rails on a piece of thin aluminum, I can miss match ans squeeze more in and they don't make noise when I open/close the drawers.
I have a small Snap On top chest which I take to the race tracks. I cut the metal rails to the exact length and mis-match 1/4-3/8-1/2 drives to what I needed and it's a tight fit. all these on the aluminum is cheaper than 1 single Hansen tray.