There is no performance advantage to LP, except that it may be slightly gentler on brittle paint.
The DISadvantage is it can be less effecient, and can starve your reg.
But ultimetly, there is no difference. Every paintball gun is tuned to a specific PSI range. Most blowbacks are tuned high, and most spoolers are tuned low.
The rest (ramvalves, and cockers) are usually in the middle.
The LP myth started with Smart Parts. The original Shocker used cheap solenoids, and could NOT run HP. It could only run LP. So, they invented a story where it make the gun more accurate.
They even put it in the patent!!
BUT... NO TEST HAS EVER shown any performance difference.
Its LP and HP is just part of fine tuning your gun to a specific range by adjusting springs, hammers, dwells, etc.
Its just like how you can get a bigger CARB for your engine, but if its too big, then you loose power and effeciency. Everything is a balance.
Nick