Until recently, I had been a happy user for a couple of years. I've recommended Muun to many CEX bitcoiners who knew nothing about Lightning. The onboarding was very easy given the double tab bitcoin/lightning. I also liked their seed backup approach that was exposing the limits of BIP39. I've only once experienced exagerated fees. Nevertheless, I think they've stayed behind, like for example with LNURL-Pay, and my go-to recommendation now is WalletofSatoshi.