The safest assumption is to consider that with the exception of documents, all items are taxable up to 50%, especially if you use courier service. In my experience, I find that you'd have better chances of not paying anything via EMS than through any courier service kasi mas "proper and documented" ang courier service companies when dealing with Customs, while the Post Office is tipong hit or miss. Yeah all items I sent via courier ay laging required ang invoice. Pero iba-iba talaga experience ng mga members dito because the Customs policies are as clear as mud.
Although some items may honestly be for personal use, I dont think the Customs people really look at that kasi for them, lumang tugtugin na yon. And it seems they dont even really know the actual duty rate - maski nga sa airport where it is clear that each traveling Pinoy has a 10K-peso duty free limit, they don't seem to know how to apply customs duty properly.
Raising up an old thread but with relevant question:
I do buy DVDs from NZ for educational purposes however, customs charges me with tax, almost 30% of the cost of material + shipping (yes, combined). Do we have any existing laws or regulations on DVD imports, particularly those for personal use?