I haven't been back to HK for a couple of years now but when i went there regularly, there were only two places i'd consider staying at on Nathan road:
- Garden Hostel (the original) 3rd floor, Mirador.
- Traveller's Hostel, 16th floor, Chungking.
at the time, for 130 HKD, you could get your own private can of sardines with a bed/bathroom/shower. that's all i needed most of the time.