If it works for you now, it's very unlikely to suddenly stop working anytime soon. It's a great convolution reverb, more versatile than many others. Go ahead and use it. I can think of no reason not to.
 
Yes, it's true that PS will not be developed further. Aleksey has even dropped his own version because it wasn't selling well. So yeh, it's a dead product. But so what? It's stable and sounds good and doesn't lack any important features.