OK.
Next step is to compare the ipLDK-300 with other system that you use in the Philipines.
And also compare the national telephone setup and regulations to other countries.
We have had some discussions in this forum where users from Africa had to use the settings from England (country code in PGM100), and other countries had to use the settings for Denmark, Europe to have the best performance.
If you will stay with analogue line, I would use the standard CLOB or CLOB8. CLOB8 can be strapped to both 300 and 600 Ohms.
///doktor