Picked up my Roc yesterday, I'm using a 16Gb card from play (Â£17.99!).
Had about 12Gb of stuff on it (~9 solid days worth of music) in the format X:\artist\album\track - took over fifteen minutes to "process" every time I started the engine - was not happy! Having re-loaded all my tracks back on in the format of X:\track it now only takes approx 25 seconds to load -much better!
Now I've got all that sorted, I can settle down to doing some real work