I just had an armored flexible toilet supply burst in the middle of the night. Lucky we were home to hear the water squirting. The plastic tube burst right through the mettalic sheath, at the connection to the fitting. I think this supply line was about 25 years old, installed by a plumber who had re-piped our house. Do these things have a limited life? Am I supposed to replace all the flexible supply lines to toilets, faucets, etc. on some periodic basis? And since the plastic burst right through the mettallic sheath, does the sheath really do any good, or are the unsheathed reinforced plastic lines just as good?
Thanks,
Bob

OK: Reinforced plastic lines
Better: Metal sheathed flex lines
Best: hard plastic lines or hard metal lines

The first two are labor saving. The top one is cost cutting.