I’ve fitted the Shark Sena Mesh Wave intercom rather than the Nolan N-Com Mesh to my Nolan N120-1 helmet. They’re identical apart from some branding but the Shark unit is £15 cheaper, and even cheaper still with the combined helmet/intercom VAT saving.
The mesh intercom connected easily with an Interphone U-com16 and gave clear comms at useable volumes. Battery life has been sufficient for a days riding.
One thing not in the specs for the intercom is that it uses 40mm speakers which fit the helmet recesses perfectly.