What is the advantage of an advanced battery charger?
I'm assuming you only want to charge NiMh and/or NiCd based cells because that's what your old charger supports. If it supported Lithium based cells it would need to have more complex electronics.

The more expensive chargers often use a higher charging current for faster charging but this means that this current has to be switched off or lowered when the cells are full.

Cheap chargers like your old charger take much longer (10 - 14 hours) to fully charge the cells. These chargers simply charge with a small current which is allows continous charging meaning, it does not need to be switched off.

When NiMh and NiCd cells are fully charged but you still charge them, they get warm. That's not a problem at a low current (as is the case with the simple chargers) but it is a problem (the cells will overheat) at a large current. So fast-chargers need electronics to detect that a cell is full and stop fast-charging it.

If you can wait for your cells to charge, by all means get a slow / cheap charger.

If you cannot wait, get a fast charger.

You could also consider buying more cells and alternate sets using the slow / cheap charger and for the same money as a fast charger.

For cell lifetime in my experience the slow charging does put less stress on the cells so that should make them last longer.