GarryB wrote:Would add that S-350 is likely cheaper... the missiles are smaller and are weight customised, so when targets are detected in close the smaller missile can be used, while targets detected further out can be engaged with the larger missiles.
the S-350 will probably have more ready to fire missiles on each TEL, but like S-300P it wont have the mobility of the tracked army systems or response times because the airforce systems are optimised as shelterised systems for use on large airfields and other fixed locations, while the army systems are intended to defend forces moving cross country and either firing on the move or from a short halt.
The Navy will likely introduce the S-350, but will also have the Shtil-1 for export and some domestic gap filler vessels (ie Russian talwars might have Shtil (BUK) or S-350).
All three branches will be ordering and having in service enormous numbers of SAM missiles so the economies of large production batches applies even if they all have different missiles.
The S350 is actually more expensive because of the active homing. Buk is command guided.
Also, S350 is already in use in the navy on the Steregushy class ships while Buk M3 (as Shtil-1) is on the Grigorovich frigate.