Call Me Daddy:
Don't know enough about the work being done in HH to really comment, I leave that to peopl like ATAdmin whom I'm told has had work done there,however :
If you have any concerns about work being done in HH consider a side trip to Bangers. Sukhumvit Soi 5 is where Jimmy Wong (and family) have their studio ... do a google search and you will see there is little but praise for these artists.
I have not been inked there but the guy who did my first tat in Thailand has been, the japanese sleeve he had was OUTSTANDING.
Something else to look out for in Thai parlours is the quality of ink used. I have seen some very dodgy looking stuff in what otherwise look like professional studio's.
As with anywhere do your homework perhaps with a little more due dilegence than you may elsewhere, whether the shop be western or Thai operated.
But who am I to give advise, my last piece of work was done by a bald guy who could not speak English had no references to any of his previous work and to top it all was dressed in a a saphron robe sitting on a dirt floor with a length of bamboo to poke in my back !