I posted chapter 4 a couple of days ago. Planning to do one a week.
The general results of putting SM4200 up on ff.net have been…good, but disappointing. There've been no negative responses, and I've even had some actual commentary back—ie, someone posting a review that actually went through the story and commented on particular points. That commentary was, I think, based on a line-by-line compare of with the version of SM4200 that was posted to rec.arts.anime.creative, years ago, but has still raised some good points.
On the other hand, while the responses have been positive and useful, there haven't been many of them.
Regarding ff.net in general…my experiences of it appear to have been better that some of you, judging from the comments you've posted. ^_^ Yes, most of what gets posted there is juvenile crap (it follows Sturgeon's Law very well indeed). And yes, the site has a deplorable habit of altering the text you post, without warning you. (I spent a lot of time working out a format for SM4200 that wouldn't get changed.)
But I've also read some genuinely excellent stories there as well.
I suspect that some people would like to see me posting SM4200 on moonromance.net instead. I've considered it. But moonromance.net has its own problems, primarily technical. (For example, cryptic database error messages when one tries to change an email address. Zero response when complaining to the site admins about same.)
In the long run, my own web page remains the primary forum for posting the story. All others will remain subsidiary.