Yes. I have The Maya going. It's a novel that's probably 50-100 pages from actually being completely written, but I've been posting it just to see what serializing a novel would look like and how it would do here.
While that book isn't published anywhere else, I do have two self-published novels for Kindle.
If you were making that much a month with yours, you were doing pretty good, but it sounds like you had the needed marketing and funnel infrastructure in place, too, which takes effort and time. I wasn't able to get that far. With self-publishing, you wear a myriad of hats and I haven't found the balance necessary to keep them all going.
I will have to take a look at how it has been doing for you. I realize not all things are equal, but I used some of my profits before I quit writing to pay a ghostwriter to write 2 novels for me (the others in that series have never come close to paying for themselves). They are unedited and I had toyed with the idea of just slowly posting them on here as is as I am really tired of the self publishing gig (all those hats, lol). I still make ok royalties though, last month being the best I have had in months (almost hit 500.00). I haven't written or ran any promotions in about a year and a half.
Are you pleased with how it is going for you, or simply continuing out of obligation since you started it?
I wouldn't say pleased, but it's gone more or less how I thought it might. There's been a couple of hits over the last three months by Curie, which has helped, and the amounts have risen from cents to a dollar or two now. I'd like to say that equates to a following increase, but that's simply not the case. No one regularly interacts on the posts other than very brief things like, "Good job," or "Interesting story." I do sometimes try to see if they're actually reading or not. For the most part, they aren't.
I'm continuing because it's been a rather consistent source of rewards, it's ready made material, and because I still have plenty of story left. Since no one has really read it from start to finish, or even got into it in the latter stages, I don't really feel any obligation to it. I enjoy putting up things that I created, like Outworlder #1, my 32-year-old pencil only graphic novel. That was fun to post, too, even though it's not that good. :)