Please see the most recent updates in the "Where did the .com name go?" thread. Posts number 16 and 17.
It's worth noting that the $5.00 pricing is only going to be up for the rest of the day, since Steam daily deals are usually only up for 48 hours. Following Steam convention, it may be on a 50% sale for the duration of the holiday sale, with a chance that it may go cheap again on the last day of the sale. However, if you want it for $5.00, you'll likely have to jump on it today.
However, they do share the same AppData folder if I recall correctly, so I highly suggest backing that up first.

Multiple installs? Am I correct in reading here that if you have the disc version of FSX, you can install the Steam version also and they will not conflict? I am thinking about dumping P3D 1.4 and installing the Steam version for all of my Orbx stuff is all.

If I have read the posts in this thread correctly, both my FSX-O and FSX-S can reside simultaneously, right?
Ok then, as a precaution, is the advice to back up my FSX config files still applicable?
More importantly, so I can fully understand this process, to do a backup of those files, is it simply a matter of copying that folder?
Thanks, NC
Its the easiest way of backup. Just copy the FSX folder to a new location. Like another drive or even into a ZIP file.
So untill There is a resolution for FSUIPC tp work with FSX SE, I see no reason to install the Steam version.