A lot of people have problems with them at first, including me, but it is worth persevering and practising a few times in the comfort of your home and soon you will wonder why you ever had a problem with them.For some reason inflating them was always a drama !!!!
And press the end in to break the seal!You only need to undo the lock-nut a turn or so. You're less likely to bend or break things then.
That'd be true of all valves though.I can't really see the point either and whilst Ive no experience I reckon they'd introduce another weak point for air to escape from :-/
The valve cores sometimes unscrew and aren't easy to tighten, they seem to leak quicker than the other types and I've got an explosively-deflated Schrader tube where I can't see any damage so I suspect the valve. I'm inclined to replace the rest of my Schrader-valved bikes with Woods as the inner tubes expire.Schrader seems to be very robust in my opinion.