I have the Datatool System 3 alarm om my 2004 Sprint ST.
It has an extremely efficient engine immobilizer and a motion detector which will allow 1 x nudge only then go off.
It is a very loud alarm.
It can be annoying if you try to start up without disarming first. It is also a two button remote. 1 button disengages the motion sensor the other the alarm as a whole.
It also has a service mode so you can work on the bike without it going off.
There is now a S4 version which is currently available. My remotes have the triumph emblem on them and mine was packed as a Triumph part.
Mine does NOT have proximity sensors I do not know if the S4 does or not bt you will get that off the website.
I do not think it is an FM remote but I am not a tech head.
It is a very effective alarm I do not know if it is the best value or not (I got mine for nothing).
The Datatool alarm is a simple plug and play straight into the Triumph provided socket.
DaveM