There are so many serviced apts...so much depends on budget and taste--and where your office is relative to available transport. Don't underestimate the need to be able to get into aircon within minutes of leaving your home/office. I stayed briefly at the Harbour Plaza Northpoint - did not take an apt there but in retrospect should have. Convenient to work on Kowloon side, yet only stops away from Wanchai, Admiralty where I seem to spend time. Very nicely appointed rooms, Taikoo Place is within walking distance and there are some good restaurants there. Royal Plaza near the Bird Market on Prince Edward Rd. has nice suites and is convenient over the KCR...but the style is the suites is a bit heavy (Napoleonic?) and the public areas seems a litttle like Hello Dolly in drag...that's unkind...but that's what I thought. Course, the shock and edge has worn off some of the glossy style and I'm less picky ;-)
My own choice was to negotiate keeping the previous tenats furnishings and taking an unserviced apartment. All in all, it has been a good choice and got me started with a few pieces but also gave me scope for buying some of my own. I found service suites had little room for furniture you might want, and no tolerance if you want your own art on the walls. That's less true for the less expensive ones, I think.
Looked at some in Happy Valley, Causeway Bay, and generally found the rates were ALL higher than advertised and full of extras. For some, the suites were depressing.
Good luck!
JJ