I can't say for sure. Its not blindly easy like double clicking on a file, but another member who's actually done it posted a thread on it not too long ago, he said looking back on it it was really easy, but he created problems for himself by rushing. I'm sure there are a whole bunch of guides around for doing so, and with the back up BIOS on the card it's practically risk free.
It will run a little hotter, but its still well within acceptable ranges, especially for the performance increase. I look at it as its basically a $370 card for $300, I'll put in an hour or two of work for $70 worth of performance wouldn't you?