I have the Stratos S with 6TB of internal storage, and I love it. I’ve considered upgrading to the V for Dolby Vision, but honestly, that feature is overhyped. I can watch the same movie on my Oppo 205 and my Kaleidescape, and I don’t notice anything missing—it’s that good.
The S model is no longer in production, so you’d have to find one on the secondary market. I ended up getting the full server setup and love having hundreds of movies available for instant playback. I do delete movies I’m unlikely to watch again and keep an Excel spreadsheet of my collection, which I share with friends for movie night selections.