To me, both are excellent and both worth having. I bought PoaL when it came out and I have oud ispahan, which came out later, on my to-buy list.
To me, they feel different. Rose Ispahan is a smoother, more traditionally (in the middle eastern sense) oud-rose combination, supersmooth, slightly sweet, with the resinous, mineral, and woody aspects of oud in evidence.
So it's smooth, but rich and more exotic (to western noses at least).
In constrast, I see PoaL as a modern powerhouse. It's a rose with lifted by a potent woody amber, similar (but much better) than many modern masculines. Extremely radiant. So in the end I think it's whether you want something more modern-masculine, or smoother and sweeter.