my sister-in-law also hired a 鍾點教 maid to do cleaning.. but the 鍾點 has been working for her for a few years lor... so, reliable and sister-in-law knows the "cleaning method" is acceptable.
I think if you hire a 鍾點 that you know well, should be ok.. but if you just hire someone for the first time... don't expect too much. Plus, you shouldn't let your maid know that is just a 鍾點... you need to tell her that the 鍾點 is your relatives ... coz' the maid will not listen to her if the maid know the 鍾點 is also someone you hired. (that happened to me when I hired a 'pui yue' and my maid refused to listen to her unless i forced her to)