Gene- welcome to the sport. I hope you have a great time which ever class you choose and stick around. I have both and I have run both, and am older. If your not in great shape, you’ll get worn out in tag. If you end up stuck on the track (inside rear won’t come up) it can be just brutal. You find out what “death grip” means, and you’ll need help to load your equipment. the speeds for tag are simply fantastic, and as said before, if new the learning curve for driving and upkeep is very steep. If you get bit by the bug bad, racing all the time, the money leaves you like water out of a fire hose. I have to agree with the advocates of the lo206, much less expensive (around here $3500 turn-key), cheaper to run (pump gas ), and maintain (forget rebuilds, sealed motor). not nearly as fast, but the difference in lap times for the really good people would surprise you. You might want to expand where you would run rather than stay local for the difference in cost. in 206 you will always be racing someone. In tag they can become parades pretty quick. You can also pick up an older euro frame, cut the back bar and reweld it to clear the chain, and have a very nice setup for very little money.
again best of luck, hope you have fun.