As long as you're ready for whatever comes, it doesn't really matter!
It really depends on what kinds of things you're willing to deal with. All dogs demand a certain amount of patience, effort and energy for all of the love and joy they give you. Puppies can be a huge handful, but so can rescues who haven't been treated well in their past.
Having owned both, as a personal preference, I prefer 2-3 yr old rescues to puppies. Puppies are so darn cute, but they are a LOT of work.
The reasons are: I don't like potty training or having to keep an immaculate house to keep the puppy from destroying things, etc.
There's nothing more rewarding than knowing you saved a life, too. I vote for a rescue.