Up till 1 month ago, my set-up for work was:
1 x Sena 10C BT primary comms / camera.
1 x Sena SMH-5 BT back-up comms.
2 x Sena SR-10 BT / PMR446 radio converters.
Kenwood PMR446 radios.
10C, not being waterproof, crapped out after 2 years of all-weather use. Sena refused to repair even though I'd have paid for repair. BT comm worked great, camera worked great. Till the unit failed.
SMH-5 still works fine now, but will only pair with another Sena unit. I have no confidence that a) it won't fail, and b) Sena will look after me when it does.
One SR-10 failed after 2 years of all-weather use. Haven't bothered contacting Sena. The other still works fine.
We got Cardo Pactalk Bolds to replace the Sena/Kenwood gear. Proper waterproof. Very good audio quality (JBL speakers), and pretty easy to use. Pairs instantly to each other by DMC once powered on. Paired easily with my SMH-5. Haven't yet managed to pair with the Sena SR-10, nor another instructor's Interphone BT unit. For the Mournes Invasion at the end of this month, me & my mate Adam and our two passengers will all be hooked up by 2 x Packtalk Bolds, 1 x Sena 10C, and 1 x SMH-5. I expect this all to work fine, with the Cardos doing all the behind-the-scenes work of connection and staying connected.
Sena gear, not being waterproof, is IMO not fit for use on motorbikes, regardless of whether its mesh function works well or not.
Good luck with whatever choice you make.