I'd like to make mine functional since it looks much the part and the rest of the arguments are debatable.
The problem is the Sierra air cylinder is too short and if you mount it in the scale position, it doesn't even retract half way.
The solution will be when we design a truly scale tail retract (I'm working on 100% scale mains in 1/5scale at the moment). If I can find a longer cylinder to replace the stock Sierra, it may work.
JG