You'll need a small philips screwdriver to take the box mountings off, neat idea to save the loco getting damaged in transit.
Initial thoughts are
a/ It looks like one
b/ The weight is very good, Hornby appear to have made the weight out of depleted uranium.
c/ Runs superbly
d/ Finish is very good, it'd be nice to have etched plates to place over the printed ones though.
e/ A quick scan against dimensions seems ok and shapes against pics again look good.
f/ Tender is from the Black Five, which is a few years old now and doesn't have quite the finesse of the loco, but theres one or two easy fixes to sort that. It certainly doesn't detract from the overall model.
g/ Well worth the money Hornby raises the bar again.
Some more pictures here