What’s your budget? The thing about older karts is, parts for the brake system are hard or impossible to get so you might need to buy a new system. I would run the Yamaha first few times out in practice.
Your budget will be consumed far too quickly in tag. Either a briggs or Yamaha would be a much better value for experience and track time. Get in touch with a local track owner to see what is offered and ask what kart shop you can get in touch with.
I don’t have the biggest budget. Probably around 6-7k. I plan on doing partial season at first to get my feet wet. But I want need to get back out on track and doing so with the lowest cost to entry would be nice. I would like the chassis to stay relevant for a couple years (up to 3 years) so maybe buying someones 1 season old or practice chassis would be easier and more affordable in the long run