With water based suspension the main PIP/pain you will feel is the white crystals and powder sitting in your muscle for a few days until it disperses. However yes you can mix them both together - I've done it many a time without problems with tren in the barrel too. Just make sure you mix it and shoot it straight afterwards, and beware that one minute it will go in as normal and the next shoot in as you hit the water part Lol

These are the two injectables that cause me the most pip. So for me mixing them together would cause unbearable pip