The quality has definitely dropped.

There have been discrete points where I would buy a Reese's peanut butter cup and go "Yuck!". We're currently in such a phase right now where I won't buy them anymore.

I really notice when they tamper with the peanut butter. But there have been a couple of times where they over-sugared the chocolate.

Normally, I would have blown it off as "getting old" except that I mentioned that I wouldn't buy one anymore and two children (14 and 10) agreed that they started sucking that year.