I leave mine in. For cleaning, I disassemble and soak the parts in water and white vinegar at 20% for an hour. I know that vinegar can be hard, but I have not noticed any decomposition/damage to the seals. I would like to find some spare seals, though. I replaced the seals in my PT2s at about the 6-month mark.
It costs a little bit, but...well, I haven't had any leak problems.