I'm still hosting, and right at two years with hookworms (about 8 months hosting a truly therapeutic dose). And 3 years, 9 months of hosting total. (I began hosting rat tapeworms.) So far, for me, it helps some. It can be a rocky road, with ups and downs. I'd still rather host than not. I'm hosting ~ 37 hookworms now, and will probably maintain that level as a stable colony. Like Gyre, I reinnoculate with 4-5 hookworms, every 3 months. I find that schedule preferable for a variety of reasons, not the least of them being the hookworm bite rashes. I believe in hosting multiple species, but haven't yet acted on that belief.
I was thinking about hosting HDC's, but that will be further down the line. I'm interested in that species because of the cognitive benefits many get from it.