I got a custom panel on my flop tunnel which I absolutely love. I also love the updated connections for assembling the tunnel, it is very sturdy and won't fall over when my buns try and knock it about. Eevee and Cinnamon have started exploring their tunnel already and really enjoy it.
my one criticism is that the opening for the tunnel seems much smaller than the one for the castle. Luckily my buns are tiny and love squeezing into small spaces anyway but for any buns that are larger this would possibly be a problem