Is it real 32 bit float or single ADC? As with conventional audio recorders there seem to be some wireless mic systems out there with dual ADC and some with single ADC, and they don't state which in the adverts.
I would chiefly be worried about the processing that the device uses for NR and ALC - can it be turned off? As I've said before (often...) I use the Rode Wireless Micro system for head mounted binaural recording but occasionally its "GainAssist" system can intrude.
Also, I wonder whether this system is tweaked for voice recording rather than flat frequency response recording. The Rode system seems, subjectively, to be pretty flat.
Lastly, 120dB SPL isn't really that good for live amplified music recording - a bit borderline.