Doesnt really matter which Tridium ... any flavour will do close to the same thing.
Cant say the same about which field devices though ... they all have their merits and failings.
Lon under a JACE works well and Lonmaker not needed as the JACE will manage the network ... BAcnet is fine too.
you just need to be able to program yr field devices somehow ... preferrably over-the-wire.
I hate being locked-in with a vendor...special licensed tools ...special 'dealer-only' channels ... etc
1 + 1 = 3 ( *** for very large values of 1)
...everybody wants a box of chocolates and long stemmed rose