I enjoy the unconventional mini-game / chase in this module. It's a change of pace and it's good to get the players on horses. That's the good part.
The bad part is that every time I have run or played this module it's gone long. Way long. It generally goes four hours and has gone more on some memorable occasions. I find that the mini-game can take a long time and the opening encounter and getting to the mini-game can take a while. The final encounter is generally fairly fast, but also leaves many tables thinking, "Wait, aren't we done? There's more?!" after the finish the chase. The final encounter is often relatively short because the party generally gets to the location in plenty of time to set an ambush / take them by surprise, and surprise is very effective.
I'll note that so far every time I've played or run this module there has been party strife during the initial encounter, with at least one character siding with the Red Plumes while most of the party sides with the others. In one session, it came extremely close to fighting within the party when the one character who sided with the Red Plumes just kept attacking the other side and ignored the protests from the other players and their characters. In another, the odd player out read the way the wind was blowing and mostly sat on his impulses in deference to the group, but it was clear that the player was straining because he felt his character really wouldn't act that way.
One minor note: Even though I prep, I seem to have an easy time overlooking the armor on the horses during the chase because the draft horse stat block (included in the module) doesn't include their barding whereas I am accustomed to NPC / monster stat blocks include items and equipment that are atypical but present in the module.
[4 of 5 Stars!]