I took out a 2 month lease on a service apartment, work from the apartment when I'm in HK, and after looking around at renting, I decided that the convenience of the service apartment won out, and I extended my lease for another 6 months.
Spacewise, I'm pretty happy with my 2-bedroom at the Shama in Causeway Bay. It's super convenient to the MTR, cabs, City Super, Park 'N Shop and lots of food joints open at all hours of the day and night. A bit $$ if you want a 2-bedroom, but the single bedrooms are about half the price.
Good security also which important to me because I travel quite a bit so it's nice to know that nobody can get into my apartment (short of the cleaner and you only get 1 person that is appointed to your apartment so you can get to know them as well) when I'm not around. My cleaner is very sweet, waters and talks to my plants when I'm not in town.
Check out the lease agreements because some are pretty flexible when it comes to making the place more homey ...especially if you are on a longer lease. Mine allows me to hang my own pictures and art work on the wall (they'll even come and do it for you. Good thing because I hated the art work they had),and add your own pieces of furniture and objets d'art around the place.
Depending on the service apartment you're in, some are also affiliated to clubs such as the Pacific Club or Kee Club which is good for entertaining clients and friends, and generally to hang out from time to time.