I bought the FoBo set about two years ago and used it for 6mths on the nineT.
As I ride the nineT every 2-3wks I found that the tubes would lose pressure in that time, so I would have to take the sensors off each time to pump up.
When the sensors are removed they need to be re-synced by holding the phone right on the mounted sensor.
(They won't pair/sync standing up next to the bike, which is strange as once paired they work anywhere within a few metres?)
The first few times was easy to do this, but then it became harder and harder to sync.
I'd have to try it 6+ times to get it to work, very frustrating. The last time I tried they wouldn't so in the end I just put them back in the box, I'll use them on my touring bike that has tubeless tyres!
I did find some twin inlet valve stems that would work so that the sensor remains in place, but they are for tubeless setups. Oh and their lightweight isn't enough for me to worry too much about balance, but check that yourself.
I think they are a great must-have addition, (just not so on tubeless tyres) but look for a more user friendly set (unless FoBo have improved their bluetooth?).