Surely Mode S equipment is cheep enough for ALL aircraft to be equipped with it,
Quick look round the markets shows about £2000 for a light aircraft mode S box and up to £7500 for more sophisticated kit. Knowing the tight budgets of some of my flying buddies I reckon they are a few years away from swapping out their trusty KT76A mode C jobs...
PS Loved the mistyped "cheep" in a thread about " Squawking"