I have used TireGard, FOBO and Garmin TPMS - all of which screw onto the Valve Stem. They are great on older bikes and newer ones for which TPMS is not available as an OEM accessory. But I would not use them when I can specify OEM TPMS.
All those add-on TPMS manufacturers swear that you do not have to rebalance your wheels when you fit them, even though they weigh 12-20 gram each. I replace my own tires and balance my wheels myself, using a manual tire changer and static wheel balancer - to within 5 grams. So, I screw them on before balancing. Triumph's is installed in the wheels, on the inside of the valve stems—nothing to lose, nothing to get nicked, nothing to rebalance to when one goes missing or on the blink. Only Tiregard comes with a security ring - another PITA because you need to remove it (one per wheel) with an Allen key when you inflate tires.
You have to physically look at the phone or keychain display to see tire pressures with the aftermarket ones. The Rocket's displays on the dash and alerts you immediately when tire pressure is low - in your face, you cannot miss it. Like a proper TPMS should.
My 2014 KTM 1190 Adventure has a similar built-in TPMS to the Rocket's- not as fancy obviously, but on the same batteries still seven years and counting.