I have never pre-released from my bindings. Too many people think of skis as something you never need to perform a preflight check on, they should always "just work". Bindings are precision mechanical interfaces, and deserve attention.
Here is what I do.
Every time I put them on:
1. Scrape and whack boot sole free of snow with great prejudice. If needed, do the same to the binding.
2. Snap the boot in, make sure that a "THACK!" and not a "THUNK!" is heard.
3. Check for lateral and rotary play.
4. Check lateral alignment. I've occasionally been able to lock a boot into a binding with it being slightly out of center at the toe.
Every night after skiing:
1. Check flex and edge integrity. Put the skis together base to base, look for discontinuities in the camber. If I've broken a ski, I want to know before they fly off my feet.
2. Look for cracks in plastic housing, this may indicate bent metal inside.
3. Snap the boot in. Check forward pressure screw to make sure it's slightly recessed with the boot in.
4. Check toe height by trying to work it up and down.
5. Check for lateral play by working the boot side to side.
6. Verify DIN.
1. Check for rust on visible parts.
2. Check for excessive wear on boot soles.