I think that
www.asiarooms.com and octopus site dont worth to pay. they provide good hotel information and reviews but dont book there because their price is more expensive than travel agents.
www.zuji.com has good prices for air tickets and it's reliable. but i havent compared hotel prices before. you may also compare with
www.priceline.com.hk. if your travel date is flexible, you may be able to bargain for a good price.
furthermore, if you want to book kl hotels, you may try a local malaysian site:
www.cuti.com.my which is recommended by my malaysian friend. it's reliable and price is quite reasonable.