[pornel]

I see no point choosing M1 Pro over M1 Air as a dev machine. $300 extra buys you mostly the TouchBar.

Air has a better form factor (no sharp edge under wrists). Better keyboard (real top row). Both have essentially the same specs. Battery life on both is an overkill. Active cooling makes relatively small difference and kicks in only in long workloads (longer than a reasonable build should take).

[reader_mode]

I use laptop keyboard 5% of the time, but I use the laptop screen as a secondary monitor constantly.

I can't judge the battery - but it's for sure going to stay useful for longer as capacity degrades.