Just built in one of these moving a fully custom loop from a Fractal Design Define S. I also have a P300A and two P600S so definitely a Phanteks fanboy.
The internal chassis is fundamentally the same as a P600S. So loads of space front and top for radiators, wide so any tower cooler will fit, pre-designed for a vertical GPU.
Things the P500A Black does worse than the P600S Grey for £50 less:
- Right-hand side panel is fixed on the P500A and a swing door with magnets on the P600S
- Top panel magnetic mesh on the P500A is flimsy and I suspect easily lost. The top panel on the P600S is very very good.
- Top power switch on the P500A does not light up unlike the P600S and P300A.
- No fan controller (unless you buy the DRGB variant)
Things it does better than the P600S
- Easily accessible front USB on the top of the case (P600S hides them behind a hinged door on the front)
- Front panel is easily cleaned
In conclusion, the P500A Black is a superb case for the money. Now if only they would make the P600S but with the P500A mesh front.