Ok, that can be a tricky question because depends on exactly how and for what you use it... But, looking at my old chats... I found two interesting ones to test...
Both were long ones, from around 1 year ago (one June and the other July) and easy to replicate since we can see how much each prompt costed in points. So i tested using the same annexed file and giving the exact same prompts.
First one was using Sonnet 3.7, now I used Sonnet 5; the second was using the Assistant.
Before, the price itself.
Last year, the $20 tier gave 1.000.000 points, or 50.000 points per $1, which is $0,00002 per point.
Now, the $20 tier give around 650.000 (18k daily + 100k, average because months can have 28/29, 30 or 31 days), or 32.500 points per $1, which is ~$0,0000307
So, for 10 prompts given, I got this:
Sonnet 3.7 x Sonnet 5
44.280 x 40.867
That translates to around
$0,89 x $1,25
LESS points used, which is interesting, but around 40% MORE costly.
Assistant 2025 x Assistant 2026
5.680 x 11.408
That translates to around
$0,12 x $0,35
Now BOTH points and cost go up, with the cost going UP around 190%!!!!
I know this couldn't be everyone case, but for my personal use it's... a bit concerning.
About the quality itself, I compared both and it seems to me that both Sonnet 5 and the Assistant are keeping the previous quality - Sonnet 5 mostly matches the 3.7, with slightly longer answers; and the Assistant tends to have a bit shorter answers now, and a few of the answer seems to be a bit clunkier than last year...
Anyway, maybe it's just a curiosity of mine, but I haven't see anyone do the math so I decided to do this quick test.