Plain old creatine monohydrate is all you need. Too many people overcomplicate things.
As long as it is what is says on the label it will be just fine for the job. You just never know
when the label is telling the truth. Creatine should mix easily without that residue on the
bottom.
Synthetek's creatine is perfect and comes with the double money back guarantee so you
know exactly what you are getting.