1. Fast mode ain't that fast
2. Large context * Fast * Higher Model Base Price = 8x increase over gpt-5.3-codex
3. I burnt 33% of my 5h limit (ChatGPT Business Subscription) with a prompt that took 2 minutes to complete.
How do you arrive at that number? I find it hard to make sense of this ad hoc, given that the total token cost is not very interesting; it's token efficiency we care about.
which is basically maxxed out quickly. So there is 2x (the first lever)
Then there is the /fast mode, which they state costs 2x more (for 1.5x speedup)
And then there is the model base price ($2.50 vs $1.75), well yeah thats 42% increase. It is in fact a 5.7x total increase of token cost in fast mode and large context. (Sorry for the confusion, I thought it was 8x because I thought gpt-5.3-codex was $1.25)
2. no if you are on subscription, it's the same, at 20$ codex 5.4 xhigh provide way more than 20$ opus thinking ( this one instead really can burn 33% with 1 request, try to compare then on same tasks ) also 8x .. ??? if you need 1M token for a special tasks doesn't hit /fast and vice-versa , the higher price doesn't apply on subscription too..
3. false, i'm on pro , so 10x the base , always on /fast (no 1M), and often 2 parallel instances working.. hardly can use 2% (=20% of 5h limit , in 1h of work ( about 15/20 req/hour) ) , claude is way worse on that imo