As Joe says, the benifit is that you gat a British style birth certificate.

When I applied on December 2, the rate was £1=78PHP
passport was 5,928
registration was 11,778 (2 fees 4,602 & 7,176)

All the requirements are as I listed previously, i would suggest you contact the embassy regarding what can be accepted as copies and what originals are needed.

There is an office in Cebu if thats easier thwn going to Manila.