Shot 4 short films and 2 commercials by using the regular finder copy and paste. Never had an issue (crossing fingers). Since I am the DP and then run to my macbook pro and copy the footage to multiple simultaneous drives I don't visually inspect each clip. I make sure the data size matches on both the hard drives and the redmag once the transfer completes, then I format the card. I will occasionally on breaks just take a look in Redcine just to make sure the clips play and I have been fine to this day. This isn't the proper way to do it but if you don't have the resources or the budget to hire a data wrangler or a DIT then you gotta do what you gotta do. If the shoot has a budget I'd hire a professional to handle it properly.