I took NOxplode for 2 cycles (12 weeks on, 4 weeks off as recommended by
BSN). I liked it, it gave me energy and a decent pump. I recently decided to try NaNO Vapor and it didn't agree with me. I took it 4 days the first week and was nauseous during my workout each time. The stuff made my stomach feel weird and I felt sick for a few hours after each workout. They also put niacin in it which makes you flush and gives you a warm feeling. I didn't notice any extra energy or improved pump over the NOexplode. In fact, I felt jittery on the Vapor, which never happened to me on the NOxplode. Finally, the xplode tastes far better than the Vapor, which had a medicinal aftertaste that lingered for a few minutes. This is simply my experience. If you like the xplode, I would suggest staying on it. If not, give the Vapor a try, you may have a better experience than I did.
I've never tried SP250 or any other pre-workout supplement so I only have the NOxplode to compare this to.