Mixed breeds are generally healthier than closely bred animals (not that there aren’t many healthy pedigreed cats and dogs).
After forty years with cats and one dog, having rescued adults and kittens along the way, I’d suggest that a younger cat is less likely to have had bad experiences with dogs before it comes to live with you. Of course, if you adopt one from a home that had a friendly dog (say from an elderly person who is headed into group living and can’t take the cat along) that would make a difference.
The recommendation for two kittens is very good. Make certain that you don’t get two males. Two females or one of each will do much better over time. All male felines can be competitive, even if neutered, and are likely to decide that marking their territory is a good plan. I have two males at present (and one female) and so far I’ve lucked out. The younger, much larger red tabby has asserted his dominance but the older one seems secure enough that he doesn’t react to being bossed around.
