I have used Olimp's Kre-Alkalyn and MST's Kreaceps. I am now currently on NeoVar. Kreaceps is a solid formulation. I particularly liked the combination of a solid per-serving dose of Kre-Alkalyn with creatine-insulin-optimizers (Rhodiola Rosea, R-Isomer Alpha Lipoic Acid, Vanadyl Sulfate, and a Cordyceps complex). NeoVar is ingredient synergy at a high level. The combination of Banaba Extract and Rhodiola Rosea ensures that creatine is not only optimally metabolized, but also that nutrient partitioning, like Easy stated, in the presence of (complex) carbohydrates, is guaranteed. For me, stacking Kreaceps and NeoVar would be it.
I would not recommend Kre-Alkalyn as a stand-alone (single-compound) formulation.
I have not tried Green Bulge, so cannot leave a more-than-just-theoretical evaluation.