There's literally no scientific evidence of Glutamine doing anything at all, along with all the other amino acids when administered solo except for maybe Carnitine. That's it. If you insist on throwing like 10g of this crap in your intra-shake, be my guest and have fun with your expensive urine, I guess.
As for crea, it works, but just go with whatever is cheapest and try to avoid any of the beefed up formulas as these are pretty much just an excuse to markup the price. I use Kre-Alkayln capsules but only just out of sheer force of habit since that's what I originally started on.