I think their rankings are fantastic, but to be honest, the suite of tools is pretty basic. They don't have anything unique like the Auto Pilot tool that Fantasy Pros does or the Free Agent Finder tool that Fantasy Football Nerd does. Those tools are really unique and cannot be found elsewhere that I'm aware of.
Some of the tools that a subscription will get you include custom scoring, league syncing, weather reports, and a trade evaluator.
4for4 has a lot of analysis articles and they do a nice job, but the analysis is often the same stuff that I just read elsewhere. For example, checking on the status for Patrick Mahomes gave me essentially the exact same thing as I read at Rotoworld for free.
They have a Streaming feature on the site that I was excited to see...at first. I assumed that it would be a tool to show me which guys I should consider streaming that week. Turns out that it's just a search option for their articles. Not exactly a particularly useful tool - especially when it doesn't produce anything of value. For example, screenshot below is what is returned when I selected QB streaming. All the articles were from the previous year - again, not particularly useful. Selecting my year and week produces no results which makes me wonder if they support this tool any longer. If not, it's probably best to simply remove it from the menu.
The bottom line is that you're not going to use 4for4 for their tools. You're using it for their rankings.