This tunnel is an absolute HIT with my kitty! He loves to play inside of it, on top of it, and half in/half out, it's really cute. At first I thought he might be too big to comfortably fit through, but I actually think he really enjoys the size. When he doesn't have the zoomies, zipping from one end to the other, he loves sitting in the cubes or in the actual tunnel itself.
One of my favorite features is the versatility of the tunnel. Specifically, the tunnel(s) can be enjoyed indoors and/or outdoors. Long story short, my cat is strictly indoors now (he was rescued from the street), but loves being outside without a leash. After relocating to a place with a balcony, which I refuse to allow him to roam freely for fear of him rolling or jumping off, I put him in the tunnel on the balcony, and he is in kitty heaven!! The mesh is perfect because he can claw/play with it without ripping, it's sheer enough that he can see out every side, and it's breathable, so it allows both air and sunlight to enter/exit. I've caught him several times with his little head back, eyes closed while enjoying a nice breeze blowing through his fur, and my heart just melts. Most importantly, I can rest easy knowing he's safe, and his safety is of utmost importance to me. We couldn't be happier.
I definitely intend to expand my little guy's tunnels in the near future, and I highly recommend for all hoomans.