The other Megapack I've read was mostly short stories. This one was almost all novels.it took a while to read.
It's a good thing Machen was such a good writer. How good? I've been reading compulsively for well over 30 years, and I can
say confidentiality that he's the best writer I've ever read. An example: The Hill of Dreams is almost entirely description, with very little plot. Normally I'd prefer it the other way around, but I couldn't stop thinking about this book. It didn't leave me until I started the next Arthur Machen book.
Like the man said, your mileage may vary. I still highly recommend it.