It is now the norm for most TacAT excercises to run as J/K interfly affairs, although most recent ones have been put paid to by J unserviceability / unavailability. When we do get to fly VTF together, it works quite well, the only issues being penetration procedures with the J's much better climb rate. SKE even works on interfly (as well as SKE can, at least).
Yes the K's are now fitted with TCAS, although a certain support authority fcuked up the wiring when fitting it so it all has to be redone - not to mention the new altimeter / RADALT requirements, which combined mean we're not allowed to use it yet.
16B