I'm seeing some frequent false truths about the steam version on here so I just want to make some corrections:
1. The only thing missing from this version is the succubus DLC, miko DLC, and the studio - everything else is included.
Glass house, metal/mech/futuristic house, additional scavenge points, and the valentines items are all there...basically all items included with free patches are there that I've noticed. I never ran the game without the official H-Patch from the illusion site, so maybe that's where it comes from and why some people continue to claim it's not there.
1.0 is the Steam version number, not relative to the current Japanese version. 1.0 Japanese version was far buggier than this and didn't have half of the stuff included. From playing I think it's pretty safe to assume this is one of the later, more stable patches of the Japanese version if not the latest.
2. The ecstasy patch for the steam version does not break the game.
The main issue I experienced was constantly seeing the download fail on the H-patch. I had to manually rerun it more than a few times before it finally all downloaded (I have gigabit fios, it's not me). Once I did though, there were 0 issues in game. My assumption is that most of the people who applied the patch and are experiencing issues used only a partial patch from a failed download.
Even though I'm missing the DLC, the steam version is the closest thing I can get to a stable develoiper copy of the Japanese version. There was a time where people used to upload the patches as they were released so I could keep a stable developer version going as a back up and then pick and choose mods at my leisure, never fearing if I didn't like something because I could easily just go back. Not anymore it seems, the premodded is all I ever see being shared.
I've tried downloading the patches myself using free vpn, but the connection is very slow and unstable. It's one thing to download at tens of kb a second, it's another for it to continuously fail while doing that.
TL
R, the steam version is the best thing going right now for me - even though it's a real shame I can't add the paid DLC.