Satun has a good reputation. Cariad was rebuilt there and most of the labour was brought from Phuket - upto 60 people at one point. I once enquired about Wavemaster, now Bousted yachts and was told they specialise more in larger boats and don't like owners to be around looking over their shoulder but there are plenty of other yards like that.
The painting contractors at Rebak, Elite, did a very good job for me last year, on time and on budget
and, providing they haven't gone off the boil (I was almost their first client) I would recommend them.
I also had some work done at Batu Maung on Penang a couple of years ago and was very satisfied. However, there has since been a change of manager and I have heard complaints about overpricing.