Kiss your productivity goodbye. Emacs has lots of half-baked features that you'll be tempted to fix with its LISP dialect. It's so much fun to tinker that you'll wonder where your day went.

The $20 I spend every month on my JetBrains subscription is easily worth it. I can depend on my IDE to be working well and not waste time on fixing buggy features. The JetBrains people are also highly responsive to bug reports.