For me, sometimes faster/sometimes slower, but there are a lot of other benefits besides speed:

* I can work in code I'm not familiar with much easier

* LLMs often identify confusion or uncertainty upfront, so I can address it earlier.

* I'm much less mentally taxed so I can go for longer at my top end.

* Meetings, disruptions, end of day is WAY less critical since I can lean on the LLM to get back into things.

* I can do something else productive while the LLM is running. Bug fixes, documentation, PR reviews, etc.