up until about a year ago I never had a problem with them, always good parts, etc... my first bit of bad luck was a sticking brand new thermostat.... since then its gone downhill
last week the batt in my trans am died. took it in to be tested before I bought one just in case. They charged it up and put it on the machine. If your batt goes less than 11V then it's bad. well right after a full charge it hits 11.003. The guy goes: "nope, your batteries good man, take off your alternator and we'll test that" So I go home irritated, knowing the alternator was good (charges fine, good voltage while running, just wont start back up). go to advance auto next day when car died..... battery failed their test, put in new one and imagine that.... its been fine since then.
as for alternates to use... see if you have a local Parks Auto Parts... They have a buttload of parts in stock (had a hypertech and stat in stock for my T/A), and their prices usually about 5-10% LESS than autozone