Kc-10s are all equipped with booms and centreline drogues, so they retain the flexibility to refuel any aircraft as required. There is a difference is the tasking, which matches receivers with the most suitable tanker at the planning stage, leaving less ad-hoc aar as the RAF do. Aircraft are fitted with wing pods when tasked to support offloads with more probe equipped receivers than UARRSI equipped jets.
Transfer rates from the boom are varied by the number of fuel pumps used by the tanker: less for fighters, more for eg C5. This is no different to a VC10 refuelling using the centreline hose, which also requires careful use of pumps dependent on the receiver.