ihave3cats,
I think when it comes to agencies it is definitely not the norm to be able to interview domestic helper candidates in person. However, Arrow sometimes has domestic helpers that are available for face-to-face interview. The agency you're using sounds a bit different in that it is run by people from the Philippines and probably the candidates that are available for face-to-face interviews have either finished their contracts and are looking for new employers or have been terminated. Otherwise, they wouldn't be in Hong Kong just job seeking. So, I'm curious to know if you've asked if the helper you are employing was terminated or is just at the end of her contract? Also curious to find out what the answer to that question was from the agency staff. I think there are few agencies who would be as honest as Arrow has been when it comes to termination. If a helper is up for rehire because of termination they are completely honest about it. I think most other agencies would just say, "Oh, she's at the end of her contract" regardless.
Also, I am curious to find out what your reason for hiring a helper is--what is your main priority? Do you have little children that need care or is it more for the domestic operation of your house (cooking, cleaning etc.). As you are quite new here (it seems as far as post numbers are concerned) it would be good to see what angle you're coming from.
My main thing when it comes to the overall performance of an agency is the agency itself. It really is "luck of the draw" when it comes to hiring a helper. Every person we've talked to in HK who has any experience with having a domestic helper has told us pretty much the same thing--getting a good domestic helper is about as lucky as winning the Mark 6. So, I think that most agencies are offering employees basically from the same backgrounds--from the same labor pool in the Philippines (or Indonesia). Some helpers work out. Some don't. That's life--same thing in the labor market here in HK--if you're a boss and you hire someone, there is always a risk that that person isn't going to be the right person for the job for whatever reason (lazy, unskilled, not the right "fit" for your company etc.) It's no different with helpers.
But, I have been impressed with Arrow's followup service--they do much more than any other agency I've heard of. They pretty much take full responsibility for the laborers they provide to employers here. If this agency that you're going through ends up being just as good, definitely give us the name so that we can have another choice for agencies to go through.