I don't know if the helicopters in Rhye's are any different than the ones in standard Conquests, but I know I use helicopters in standard Conquests an awful lot when I play island maps. I simply find it much much easier to use helicopters to transport three TOW Infantry units to a newly conquered town than it is to correctly time and keep track of transports full of Mechanized Infantry. (Using the re-base option, not the airdrop one. With the re-base option it can reach any part of the map, and it's cargo stays with it and doesn't use up it's movement - IE, you could put a TOW Infantry unit into a helicopter, re-base the helicopter, wake the TOW Infantry and then fortify him all in one turn.)
Of course, this is only on island maps. On continent maps, it's much easier to use Mechanized Infantry and railroad infiltration than Helicopters and TOW Infantry.