There are lots of us who've had ML's longer than 16 years and many of us (including me) have had to go thru the process of getting new panels. When you're buying ML's used, you have no idea how they've been treated and what kind of environment they've been in... Humidity, smoke, etc. will dramatically shorten the lifespan of any ML ESL panel. Getting the panels replaced is a somewhat painful process when you're in the USA and more so now that ML has increased the price of new panels dramatically and we all know that in the UK, the dealers charge even MORE for replacement panels and you can't get them directly from ML.. So, not a "doom merchant" here, just trying to inform the OP....and glad you've had great luck with your SL3 panels... Not all of us have been so lucky. And I've venture to bet that if you got new panels for your SL3's you'd notice a dramatic difference... The deterioration happens very slowly and if they both deteriorate at the same time, it's very hard to discern that they panels are not sounding their best.