Simple, for what I'm doing Opus 4.6 (and before that, Opus 4.5) are just much better at following my instructions and achieve consistently better results.

From what I've been gathering, this split in success seems to depend a lot on the types of tasks, the domains / programming languages / frameworks used, and style of prompting.

I couldn't get 5.2 to follow instructions for the life of me, even when repeating multiple times to do / not do something. 5.3-codex was an improvement and 5.4 while _usually_ decent still regularly forgets, goes on unnecessary tangents, or otherwise repeatedly stops just to ask for continuation.

Sure, I'm paying 3x more per request, but I'm also doing 5x fewer requests.

Or well, used to. Still bummed about them dropping 4.6.