just looking at the scouts (in pictures, games, models, some short stories) they are not the heavy meatheads that normal space marines are.<br/><br/>they are trained in the 10th company (usually) to gain experience and to relay information and... scouting intel for their more experienced battle brothers. I'd put it at being in a green beret's hell week for *years* on end. They are given their implants and some indoctrination to prep them for the geneseed. The washout rate, while not spoken of a lot, is rather high, due to deaths in the line of duty, training, just getting to the next day. The last washout point is having a bad reaction to the geneseed. this is unusual because most washouts are pinpointed on this with their cyber augments. There is a short story in "Let the Galaxy Burn" compendium that is about a space marine serf who resents his lot due to a geneseed reaction... twice.<br/><br/>thats about all i know or have picked up about the subject.