Redeemer of Souls is pretty good, I've only listened to it twice so far, but I do like it. I think Ian's bass playing is possibly the best bass sound I've heard on a Priest album, ever. Scott's drumming is outstanding as always. Rob's vocals are very good. I had read reviews that he was only a shadow of his former self, and I guess if you compare it with Painkiller, then yeah, it's a step down, but compared to his solo work in Halford or Fight, he's doing just fine. The screams aren't quite as high as before, but it's still very good.
The guitar work is probably the most spotty. I'm not saying that as any sort of a slam on Richie or "I wish they still had KK", so don't take it that way. I just think that in places, some of the riffs and even the solos are a bit of a yawner. NOt bad by any means, but certainly nothing that made me say "HOLY SHIT THAT WAS AWESOME!"
But, again, I've only listened to it twice so far, I plan on giving it full attention later this week and I'm sure with a few more spins, I'll like it more.
Overall, a very good album, definitely better than Nostradamus and at least as good as Retribution.