Yup all true and entirely understood before purchasing the temperature controller (I already owned the pot). That said, as of right now I am doing 2 steaks which fit easily and I used a thermometer to check the consistency and it seemed reasonably good (+/- 1 degrees) everywhere I looked. If I really like the outcome I will likely just invest in an Anova or similar rather than add a circulation pump.
It's an experiment and I am having fun with it.