ok so i ordered another rio car, i have 1 20gig, 1 30gig and the other 50gig that has nothing to do with this post, i got one for my dad the 30 gig becuase thats all they had left, i have this 20 gig here, nowmy dad dosnt have that much music nor dose he care about having a lto of space. so what i wanan do is order a 4 or 5 gig drive and put it in his, then take the 30 gig out and pop it in the 20 gig unit or vise versa which ever works outs better, this is possible correct? and i dont have to do any messing aroudn with drive stuff it should just be plug and play? and all i gotta do it drive work on the other unit? let me in on the inside information. thanks