Haven't messed with it since 2027.0, will be giving it a try with 2027.2's release (and its promise of additional deployments between patch versions).
The issue I've been having with it in the MEP context has been mostly sunk cost fallacy - a lot of the queries or simplified processes I would want to ask it to do have already been fleshed out via Dynamo scripts or industry add-ins like Ripple, and by this point I've got a library 10+ years deep. It's hard to trade in those deterministic workflows for something that mostly works.
I'm somewhat excited for template application. Some projects we split ductwork and piping into separate views. Sometimes Controls gets its own view as well. Sometimes we're requested to plot in black and white. Sometimes View Ranges are just *weird* in the context of a particular project. It'll be nice to template control using natural language to match project requirements.
What I 'want' it to do is to be able to resize valves and certain fittings contextually - if the piping's determined to be under/oversized, to intuitively pick the most suitable correct size in the content library when the piping's changed instead of having to go back through after the pipe resize and correcting accessories post-hoc. But that's surely not going to be accessible for a while given the current speed of commandset deployment?
I also want to see if it can intuitively read naming convention and parameters to determine Fire Rating status of wall assemblies when architects decide that the Built-In Parameter intended for that exact usage is unimportant 😃 , so that I don't have to craft a ridiculous filter structure for each architectural firm to make sure I have all of their ratings visually identified.