IME the Asahi support page is spot-on: There are a couple of yet-unsupported features (DP-alt mode being a big one), but any feature listed as supported will just work without hidden gotchas. I find this a big contrast to other devices, which will often "work" but have annoying little quirks here and there that are workable but can feel like a downgrade compared to Windows.
There's some room for improvement, but that is purely relative to macOS. Asahi still solidly beats other x86 devices (other than the low end ones you wouldn't do development work on).
One issue is that idle battery consumption is higher than on macOS (an active area of improvement though [1]), which you'll notice by an M1 laptop discharging by about 12% overnight when macos would've eaten maybe 2-3%. Not a big issue normally, but can be inconvenient if the device shuts down due to empty battery overnight.
During more passive uses at daytime (e.g. playing music), the display tends to be the biggest power hog. Not really Linux-specific, but I actively turn off the screen when not needed hence (KDE lets you configure the power button to do so).
[1] https://social.treehouse.systems/@chaos_princess/11498433865...