Can anyone reccommend a good dive centre in Phuket??

Am planning a trip to Phuket in August - Yes I realise its not the best time of year to go!!
Can anyone reccommend a good dive centre to dive with, i.e day trips to local dive sites, perhaps a short liveaboard etc.
We are 2 experienced divers who do not want to be tagged onto an open water course.
Any ideas??