The GB2P is definitely more forward in the mids and has a slightly warmer signature. It has a more surround type effect.
The L4 can easily have to much bass making it a bit one noted. But can be tweaked to make it more enjoyable. I had to turn off Dolby Atmos adapt sound as it just made the bass and treble to etched.
So this is a TWS that will likely need to be adjusted to get it to where you want sonically. As compared to GB2P which is essentially designed to have a certain signature and the presets which are limited but easy to use.
Think using a Swiss army knife with every option versus a jack knife with a single blade

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