We've found that no one will use the lower section, but it's needed for stability for when they are happily jumping to the highest levels.

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[updated on 2009-01-30 09:55:49 GMT]:
They love the top levels for lounging about

Pros: none

Cons: none

Anything to keep my kitties away from sharpening their claws on the couch, and give them a spot to hide out in is a major plus!!!

Pros: attention keeper

Cons: none

We have a couple cats and they have this downstairs. They love it, they sleep in it even! lol
Cool thing if have cats....

Pros: Lots of playtime

Cons: none

both my cats love to lay a watch out the window for long lengths of time and then they curl up and take a long long nap.

Pros: cats love to climb

Cons: ?

This is such a great design! It has plenty of areas for your cat to lay down in, as well as snuggle up and take a nap.

Pros: great

Cons: none