Standard cast pistons may require additional maintenance due to them cracking under stressful situations. However, JE Pistons do not. Once they are installed into your engine, they do not require any special maintenance to keep them in their best shape. You only need to keep up with your vehicle's general maintenance schedule.
JE only makes forged pistons which are stronger and more durable than the OEM cast pistons in vehicles. This means that they are less likely to require replacing when you run them in your modified engine. They are less likely to crack or warp than the competition's automotive pistons as well. This strength and durability combined with the lack of additional maintenance makes JE Pistons an excellent buy.
In the unlikely event that there was an engine failure caused by something other than the pistons, you would have to replace your JE Pistons. They are designed to work within certain specifications and if there was something to happen to the engine their strength may be compromised. This is a precaution considering that JE pistons are an important engine component. Regardless, for however long you use your modified engine with JE Pistons you will not need to do any additional maintenance on them.