I think if you can put together a cat-run, then that is the ideal, as it allows the cat to enjoy the outdoors, while being protected from other animals, humans and dangers.
The garden cat proofing is done by having 6-7ft high fences. Then at the top of the fence, all the way around the fence, you put a netting that goes up and then curves inwards. This makes it incredibly difficult for a cat to get out. It does work, however, trees can be a big problem due to their ever growing branches.
Overall, a cat run is cheaper and more secure.
Bad bob is your cat a pedigree?
Some pedigree cats are highly susceptible to diseases. They simply dont have the genes (in-breeding) or the immune system to handle it. You send them outside, they kill a few rats, pick up a disease and die. It really is too risky. All the breeders of Maus and Bengals Ive been in contact with, all advocate keeping the cats in captivity. Not a single breeder has stated that they would be happy to allow their kittens/cats to roam the streets.
Gurusan has lovely cats. He keeps them house-bound, because he knows that those are not the sort of cats you allow out, to associate (and possibly fight) street-wise moggies. Pedigree cats cannot be treated in the same way as moggies.