I signed Reyna up right away when I got her for a health plan. It covered all dr's visits, tests, and vaccinations. Also they give a % off medications, surgeries etc. A set amount is debited from my account each month and I don't have to worry about paying every time we go for a vaccine or check up. Of course after she turns one year, I'll rethink whether or not it is cost effective any more....probably won't be as they do not need to visit the vet quite as frequently.
Hope this helps.