The first point of reference for any analogue photographer in Bangkok is Kitty Chirapongse's excellent and comprehensive "Bangkok Film Labs" webpage which is updated annually. That's the quantitative, but what of the qualitative? The only way to find out is to try the developers' services and form a very unscientific subjective opinion. YMMV1, as they say.
HYPER DEV, AUGUST 2021 (CITY IN LOCKDOWN):
https://www.facebook.com/HyperDev/ , Line: @hyperdev, 097 121 4805.
Selected: Fujicolor C200 - Standard C41 development and high resolution scans.
Report: Follow the instructions on Hyper Dev's FB page and either post or deliver your film to their shop front at Charoenkrung 30. It is easy to find. On the one-way street, go past architects Miw Jitrasen Aphaiwong and Phrasarot Ratnanimman's Bauhaus/Brutalist/Art Deco style statement, the Grand Post Office (and home to the Thailand Creative & Design Center). Proceed past Bangkok Photo XXX is also within one block. Note that HYPERDEV's opening time is 12:30hrs-18:00hrs and they accept film (in a suitably labelled envelope) pushed through their security grill outside normal hours.
Results: The scans are featured in The Canon A-1 in Thailand.
1. YMMV - Your mileage may vary.