Which regulator to Buy?

I have just purchased an Iwata HP-CS and have found out that I should also have an air regulator. I have checked Iwata and Badger for a regulator/water trap. Any ideas on which is best?

Any regulator/moisture trap that is of good quality and adjustable will work fine.

Badger and Iwata do not make their own regulators anyhow.

Thanks, I appreciate the answer.