My favorite crate is the plastic petmate crate. I do not however like the heafty price tag for the size I need. I will eventually have to bite the bullet and buy a plastic crate for airline travel, but Im going to wait.
So far my puppy has 3 crates. Two large wire crates, and 1 medium plastic. One of the wires is Rileys old crate, and I Love it! It is really strong, secure and well made! The other is another large wire crate (one for upstairs and one for downstairs) that I got a great deal on. It is however pretty cheaply made, and Im not the biggest fan of it. I will train the puppy to respect crates, so I dont see an issue with it. However any dog that wanted to could probably escape from it.
The medium plastic is for car travel and for him at my work. He will grow out of it soon, but again I got a good deal on it and I can use it for future dogs too.