Great fun! Has some issues that still need to be ironed out, also needs more multiplayer maps and general multiplayer QOL features (they're in the works). Complaints about the price are, in my opinion not justified. Comes with 3 full faction campaigns (Starcraft 2 for $10 more in the day only came with one, had to pay for additional faction campaigns). There was definitely a lot of attention paid to the campaigns. Challenges are fun too. They're committed to adding more free content with time as well (challenges, game modes, multiplayer maps etc).
Gameplay is great. Runs smoothly. Some minor pathfinding and AI issues but also being worked on. It's simpler than some RTS, less base building, not as complex as COH but lets you focus more on battle and map control strategies. After 60+ hours as of writing this review I'm greatly enjoying multiplayer and feel I could sink as many hours into this as I did Starcraft 2.
I've never given a game 5 stars because to me that equates to perfection or near it. As a fan of RTS for 20+ years, I think it's great.