Yep... that's true, but I know them both and imho the ride to Satun is more bad... also because of the sheer amount of speeding vehicles. And never forget... the best places inside a Minibus are in the last row in the back... 😁
First choice should be Bangkok Bank, try the branches in the tourist places... Malls, Shopping centers etc. Or... to save time and nerves... look for an agent... 😉