So, bought this last week to put into a Shoei full face helmet and link to a Garmin Zumo XT Satnav and Samsung phone. So far, really pleased.Helmet fitting: This was the part I was worried about but just took about 30 mins. Helmet had foam inserts where the ear speakers go, which I didn't know were there, so just removed them and used the supplied sticky pads to insert the speakers. With my set up they don't press against your ears but still quite audible. See below. The supplied bracket slipped fine between the helmet shell and the padding to attach the actual unit. The semi-rigid microphone fitted fine under the helmet padding and is placed inside the chin guard. With this helmet, all the wiring could be hidden under the removable interior padding.Instructions: OK to follow and the quick guide is useful.Controls: Buttons are quite accessible, even with gloves on, but TBH would pull over to the side of the road to do much more than adjust music volume.Sound Quality: Surprisingly good for music (after using hardwired buds for years). You can still hear the bike engine revs' and there is some some wind noise but you can still hear the tunes with a good bit of bass. Admittedly, I'm listening to rock / metal which probably helps. Satnav instructions are a bit CB Radio but I suspect that's the satnav more than this piece of kit.Battery: had a brief 80 mile / 3 hr run tonight with it switched on and it recharged within 30 mins so looks OK.Bluetooth connectivity: once powered on, no issues and tells you that.All-in-all firmly recommend. All the connections look waterproof but haven't tested that yet or the inter-bike connectivity as I tend to ride solo.