Both methods have their uses and will both probably be good in different situations.
Personally I mainly transfer troops around to provide a fighting force at the new location.
I would usually also have to provide the gear from that some initial point.
For me transferring WITH their gear would be more useful than otherwise.
In other situations it might be good to have them leave their high tech stuff behind.
Personally though I would just decide who I was sending and give them whatever I wanted them to take, if I wanted them to take no high tech gear I would take it off them.