Hi all,
This subject came up a while back on the ORBX site. Holger indicated it didn't make a significant difference but for accuracy sake, here is the ORBX official line on this question:
Copied from bottom of Page 6 of the ORBX SAK User Guide as it appears in ORBX Central:
FSADDON - Tongass Fjords X
Tongass Fjords X is an earlier landscape add-on created by the lead developer for SAK, Holger Sandmann, and is distributed by FSAddon. The southeastern boundary of SAK is specifically designed to seamlessly align with the northern boundary of Tongass Fjords. The only step required to achieve full compatibility is to ensure that the two Tongass Fjords entries are below the block of ORBX entries in the FSX scenery library menu, meaning at lower display priority. Tip: use the Scenery Library Insertion Point option included with our FTX Central control panel (described in this manual) to make this step easy and permanent.
Rod