langwadt and beanflying, an update on these modules.
I ordered 5 of them and they work very well. If you design your circuit board to match the input and output terminal spacing, they are easy to attach to the board.
The only thing I did not like about the module is the pot that is used to set the voltage. Pots tend to have an effect on long term reliability of circuits. I took the pot off of one of the board and ran some tests.
If you replace the pot with a 21K ohm, 1% resistor, you get 3.3 volts output. If you use a 37.4K ohm resistor, you get 5.2 volts output. An 0603 resistor fits perfectly across the two outside pads that the pot uses. The low side of the pot is tied to the wiper so putting the resistor across the two fixed terminal pads duplicates the pot functionality. I didn't test to see what value resistor is needed for any other voltage.