There is no such thing as "Maintenance Free" - with anything. Powerpoles are more than capable of transmitting the power we need in F3A (and for large electric 3D planes as well).

You need to check the metal for degradation. It happens at the tips. A little is OK as the connection should be over the length of the metal connector and not just the tip.

However, you need to be aware of any fatiguing or decreased spring load in the connectors. Over time (theoretically should be a long, long time) the metal can 'relax' a little. If you don't feel a good, solid connection when making your connections you need to check the engagement of the metal. All it takes is a small screwdriver/hobby knife to make an adjustment. Otherwise you have a soft connection and possibility for ARCs.

Same goes for Deans' I imagine - they also use a spring force and they also degrade over time.