.. for some reason i often get corrupted files and folders and such.. they appear to copy onto the card fine, but then i go back to see if everything is set up they way i want it and there is wing-ding font and grayed out folders and fileds and all sorts of wierd things??..
This is an unwanted side effect of MLC type cards. Since several bits of, apparently unrelated, data are stored in one cell as a multi-level voltage (hence the name) the more times you change 1 bit of data the greater the risk of another bit of data becoming corrupted when the multi-level voltage is read and written back as not quite the same value.
It's storing digital data using analog voltages - prone to error and noise.
I use a 1GB (non-MLC) card attached to 3 different PCs via 2 different USB-to-SD adapters, on both USB1.1 and USB2.0. And I move and rename files and folders, in-place edit ID3 tags - treat it just like a disk drive - without any problems at all.