I had different ML speakers for years and never had a panel go bad. I still have ML speakers in my surround sound system and they are at least 15 years old. From what I have heard the panels have been known to go bad if you over drive the speakers. Before you do anything I would contact ML & see what they have to say. It could save you a few bucks.
Best speakers to replace Martin Logan CLS
I am fortunate to have possessed a pair of ML CLS IIz for the last 10 years. They’re in an open living room (extends to kitchen and also the rest of the main floor of the house ~ 1400 sq ft). I love the sound and I listen to a lot of acoustic/jazz. I feel like the more power I feed them the better they sound. They’re being powered by 200W @ 8ohm Monolith amp. I’m also using 3 subs with it with crossover set at 80Hz. Although they sound great but I always worry the panels will go bad at any time due to their age. I do not plan to replace the panels if they go bad, but rather I’d like to replace them with a different pair of similar or better sounding speakers. From what I’ve read, these seem to be the speakers that I might like: Harbeth 40.1(2), Eminent Technology LFT-8b, used Soundlab Majestic 545, used and restored Quad ESL 57. I’ve ruled out Magnepans due to WAF. I almost bought a pair of Apogee Duette Sigs after hearing but backed out due to similar concerns with the CLS (panels will go bad at some point). I’ve also looked at some other speakers like Revel Studio2, Focal Sopra No2, Legacy Audio Focus/Signature, Spatial Audio, but I’m not sure since I’ve never heard them. Budget is up to $10k (prefer to buy used) but probably would like to stay under $5K. Please advise.