Starting black powder shooting with a flintlock is like learning to play basketball with a 12 foot basket. Not a good idea. Maybe fun at the start but it won't last long.
Flintlocks are tricky; it's best if you start with percussion and learn about the powder, patches, lubes, caps, etc. That will get you a good knowledge base. Then get the flinter and prepare to take another step in knowledge. You don't need to be trying to tune your lock while you're still working on a powder load.
The Traditions guns are starter guns. I hesitate to say good starter guns because frankly they can (I said can, not will) leave you with a bad taste for black powder shooting. Some folks get a taste and then go after the high quality stuff and others just say it isn't worth it. And some folks stay with the Traditions guns as adequate for their needs.
Read the stickys at the top of this forum; much excellent info about black powder shooting there. If cost is a real issue, get the Traditions gun but keep an open mind about the fact that you're starting with the low end of the available market. Don't let the fact that it's an inexpensive gun deter you from continuing.
Rereading the above - it seems awfully negative about Traditions and I don't mean it that way. They make very good stuff. It's not the top of the line, but you're not paying for top of the line either. All I'm trying to say is, keep your expectations in line with your wallet and you'll have a good time.