I have used pure form creatine for 25 years on and off. I know it works but it is hard on my guts and TP supply. I boost it with citrulline which they say can actually replace creatine. I have not tried citrulline alone yet. I just ordered kre-alkalyn powder to replace mono c and will try it at 4mg a day which is twice what they say to use because it replaces regular creatine at 10 to 1. I find that hard to believe so I will start at 4mg and see what happens. If it works for me I will probably stop the mono creatine all together. Not really much help but that is all I know right now.
In my opinion, I had the most success with creatine-nitrate, however, CN isn't cost effective in the long run, so I tend to stick with creatine mono. However, creaIGNITE has mono with MCC and Orotic Acid, which are relevant for improved absorption and improved ATP stores. Any form of creatine paired with Orotic Acid is a smart pairing, the two work in synergy really well. The price is reasonable as well Genomyx CREignite (30 Servings).