My kiln came with a proportional control much like (probably the same) as used on an electric cooker. Not as good as your PID controller by any means, you have to mentally guess what to set it to so it heats/cools at the right speed. Much easier just to change the setting.

I'm figuring after we move I'll put a PID controller on mine but was thinking of making my own so I could load a profile (up to cone__ in XX minutes, hold for YY, then to cone__, etc.). That way I can be off doing other things while it does a full cycle and then shuts down.

Anyway, future project for me.