There are two studies (one out of Manitoba, and one out of Univ NE Lincoln) that show superior solubility compared to creatine mono (were talking very significant results). There is a ceiling when it comes to creatine saturation. The best thing you can do to make a superior form of creatine is decrease the time it takes to reach that ceiling.
The only other benefits are a form that reduces gastric issues (which a better solubility will do), and perhaps reduce the extracellular/intracellular water ratio (which as far as I know only MCC has been shown to do).
There are currently no studies on creatine nitrate solubility, only a patent. It's possible it has greater solubility but at this point the evidence lies in favor of creatine hcl. I know Ron's team was working on funding a study. Not sure whatever came of it.
To answer your question though, creatine is creatine. Creatine itself doesnt change, only the molecule you choose to bond it with. Nitrates have awesome benefits and people should use it. And right now there are not a lot of supplemental options when it comes to nitrates and last I checked it's hard to come by beet root juice at your local grocer, and I dont want to eat 6lbs of spinach pre-workout and **** my pants half way through.