Crossfire is easy it is just the people that never done it and are scared to try something new that claim it is dangerous etc LOL but it's really easy power off system plug in second card connect CF/SLI Bridge reboot and select enable CF/SLI in the control panel LOL.
This, but its not a good idea to Xfire 2 mid/low range cards anyhow, I mean, whats your upgrade path then if its not enough power?
This is really just a question as to performance. Not really anything solid yet. I wasn't too hot on CFing 7750's anyways, because I may CF a 7850 if/when they come out. Answers pretty much summed it up though, VF low end card is not a good idea. Maybe mid-ranged.
Really appreciate that you are willing to help though!