An understated factor in choosing your air-con (portable or otherwise), is the ease of removing, cleaning and reinstalling the filters. On that note, I strongly recommend the Trentios portable air-cons SIN-TP9/15, SIN-TP7/14 and SIN-TP1/10.
Most portable air-con filters are always irritatingly difficult to remove and fix back (ie. poor design). Only the Trentios SIN-TP9/15, SIN-TP7/14 and SIN-TP1/10 models, have filters that are ridiculously easy to remove, clean and and reinstall.
15,000 BTU
6-in-1 Functions :
Cooling, Heating, Fan, Dehumidifying, HEPA Air Purifying, WifiAuto Air Swing
Touch-screen controls with LCD display
Wifi-enabled with smartphone control (optional)
Weight: 29kg
Dimensions (mm): 350W x 535D x 600H
http://www.trentios.com/products/portable/#hybrid
Edited to add :
The Trentios (Singapore) website says now got special promotion
40% discount, with free delivery, free installation and free 6 years warranty. That's a crazy ass good deal.
http://www.trentios.com/promo/