I have an odd relationship with Lumley's work. Having first come across him in Tales of the Cthulhu Mythos, I was initially interested in him simply as a Lovecraftian writer, which is problematical at times even within reference to his Lovecraft-related material.
As with Derleth, I feel that his work is very uneven. A lot of it I find to be at best pulp (in the at least ambivalent usage of that term); full of flaws and at times shoddy writing, yet often entertaining, and at times quite good.
With the Necroscope series... I found the first two (initially) very entertaining, but bogged down a bit with the third... i've not gone beyond that, though I own most of them (there may be a recent one I've missed). I still like much that is there, but am a good deal more critical than I was when younger, so am less taken with them than I once was.
On the other hand, in a recent rereading of some of his Lovecraftian material, I came out feeling a good deal more positive about things that I had initially quite disliked; largely because I was looking at Lumley himself, rather than through a Lovecraftian lens, and so was aware of other things he was doing with the material, some of which was quite entertaining in its own right (e.g., the obvious -- for those aware of the book -- nods in Beneath the Moors to Lloyd's Etidorpha, which I had not even heard of when I first read the book). Also the parodic elements of some of his stories of this sort, where he was, quite simply, having a good deal of fun with the tropes. As long as these are taken for what they are, they are often rather good things of their kind....
