Buy a stouffer strip!
Those aren't a bad start, but here are my thoughts:
1. No glass/vacuum, so they don't make great contact with the emulsion.
2. It's shooting through film the stouffer strip is printed on, which will filter some of the UV light.
3. The full size exposure calculator may take a bit more time, but it's exactly the method you will be using. Same ink, no film, etc.
That being said, we do still use ours every so often if we are testing a new emulsion.