I will leave the others for the CX, BX, and America. The Oro is actually a term for a number of freewheels. Some are G.S. Corsa Oro, the best tolerances of the bunch, you will probably not win a auction for one of those unless it is mistitled. The Regina Oro is the last, better than the Extra Oro which is just an Extra body with Oro cogs. Splined bodies are later than the "two prong" units. I would suggest a Phil freewheel remover for the splined body, as removal of the axle locknuts and washers are not required. There are also two types of bodies throughout the range, one is designed to allow for a 13-17 five speed, basic difference is that the largest position unthreads on a single land, verses the last two positions. At the end there were some 12t cogs made, they will also fetch notable money.