Seriously. Programmers making >> $100k hem and haw about upgrading a tool they use 10 hours a day. It's worth it to upgrade for $100 even if you use it for a week, let alone 6 months.
That seems optimistic, the M1s were already discounted $65-150 earlier this month. I think the decider here would be simply having an M1 if your workloads benefit from it.