They're okay. I had high hopes for Ｍ after watching the PV on YouTube for Renon「レノン」which was awesome!! But I listened to a handful of other songs following that and only liked Hinadori「雛鳥」too... *shrugs* But Masakazu DOES have a wonderful voice at least.
Indeed hope he continues, hard to say if he will though (he hasn't really singed for any other band than M anyway?) Wonder why they decided to quit, I don't think their actions before announcing disbanding really fit with it anyway so I'd guess something must have happened recently.