I encourage you to test any RNG implementation you find with, either
- Practically Random, or
- L’Ecuyer’s TestU01 (“Small Crush”, “Big Crush”),
but preferably both. Daniel Lemire wrote a blog post on Testing non-cryptographic random number generators and also provides a GitHub repository with the instructions needed: GitHub - lemire/testingRNG: Testing common random-number generators (RNG)
@mecej4 referred to these tests recently, in a separate Discourse thread.