The pay-per-use API sucks. If you end up on the $50/mo plan, it's better, with caveats:
1 million tokens per minute, 24 million tokens per day. BUT: cached tokens count full, so if you have 100,000 tokens of context you can burn a minute of tokens in a few requests.
Not really worth it, in general. It does reduce latency a little. In practice, you do have a continuing context, though, so you end up using it whether you care or not.
