Wire crates are ideal for drying dogs in. The reason? SIMPLE! AIR FLOW! If the air cannot move past the dog there is no way the dog can dry efficiently. Fans work because they move the moist air away from the dog. When using a heat dryer these cages prevent pets from overheating because the air cannot get trapped inside. Plastic bottoms are easy to clean and do not get hot like metal ones will.
Vari Kennels are great for traveling, but are not very good for drying dogs. They are ventilated to a degree, but not enough to allow enough air to move past the dogs and this slows down drying by trapping the humid air in the immediate area of the pet. If you are using a heat dryer these are REALLY dangerous because they trap the heat in with the dog and the temperature can get hot enough to cause injury of death.
Cages like this one are designed for puppies, but work great for drying. They come in several different sizes and even though they are expensive they are worth it if you can afford them..
I use one of these cage bans for drying. It divides into six cages or each level can be opened up so there is one cage large enough for a lab or golden retriever. By hanging fans on one end of the bank I can get as many as six dogs dried at one time with only three box fans.